A lechi for an eruv may be of any thickness and any width; even a string or wire may be used, as long as it is sufficiently tensioned so as not to wave in the wind.

A lechi for an eruv must be less than 45 degrees from vertical.

Psik reisha d'la nicha lei (halacha whose violation you don't intend and from which you receive no benefit) is not permitted.
Example
You open the refrigerator door on Shabbat and the light comes on.  This is forbidden on Shabbat and Jewish festivals, even if you don't want or need the light. 
However, you may ask a non-Jew to do an action for you that will be psik reisha d'la nicha lei.
EXAMPLE
 You may ask a non-Jew to get your jacket from the car on Shabbat or a Jewish festival, even though a light will go on, but only during the daytime; if it is night and the light would be needed to find the jacket, you may not ask.

The blessing over putting on the talit gadol is lehit'ateiph ba'tzitzit.

To put on a talit in the morning:

• Say the blessing lehit'ateiph ba'tzitzit.
• Put the garment over your head and down to your nose.
• Gather the two tzitziyot from the right side and the front one from the left side and swing them over your left shoulder (you do not need to bunch up the talit before doing so).
• Wait for at least 2 ½ seconds and say the appropriate verses (see a siddur for the text).

The seder table also has a stack of three matzas (matzot), representing, among other meanings:

• Cohen-Levi-Yisrael:  The three divisions of Jews
• Abraham-Isaac-Jacob:  The three forefathers

These matzot are used later in the seder for the steps of Motzi and Matza (top and middle matzas); the middle matza becomes the “Afikoman.”

You may use a car as a part of an eruv, as long as:

• The bottom of the car is within 10.5 inches of the ground, and
• One side of the car is in line with other parts of the eruv, such as with an actual wall, lechi + mashkof, or steep slope.

 

All fasts start 72 minutes (normal time) before sunrise except for the Ninth of Av and Yom Kippur.  These include:

• 17th of Tamuz
• 10th of Tevet
• Tzom Gedalia
• Fast of Esther
• Fast by a groom and bride on their wedding day
• Fast for first-born males on the day before Passover. This includes first-born cohanim and Levites (levi'im).

There are three criteria for Pidyon HaBein:

1. First child born of a mother must be male.
   Note If a woman miscarries a fetus that has already developed limbs, any male child born after that is not considered a first-born male (bechor) and no pidyon is done.
2. Boy must not have been born by caesarean section.
   Note A boy who was born normally after his brother was born via caesarean section is NOT a bechor.
3. Mother may not be the daughter of a cohen or levi (priestly family or assistants) and the father may not be a cohen or levi.

Introduction to Fast Days
The purpose of Jewish fast days is to make us reflect on our behavior and improve it by:

• Eliminating negative actions and thoughts, and
• Taking more care in our observance of the commandments.

God told the Jewish people on many occasions that He did not want their pointless sacrifices or fast days but rather wanted the Jews to improve their behavior. If people fast but still have reprehensible behavior, the people have missed the point and purpose of bringing sacrifices and having fast days.
All fast days may be circumvented for health reasons. Consult a rabbi.
Fast days come in several varieties:

• Major fast days: Yom Kippur and the Ninth of Av (Tish'a B'Av). 
• Minor fast days: There are four minor fast days; see below.
• Fast for First-Born
• Individual Fasts

The Major Fasts
Yom Kippur and the Ninth of Av begin before sunset and are both slightly longer than 24 hours. Yom Kippur is a festive day while, on the Ninth of Av, Jews mourn for the destruction of both Jerusalem Temples (the first was destroyed by Babylonians; the second, by the Romans). On both fasts, it is forbidden to:

• Eat or drink.
• Wear leather shoes (but you may wear any other clothing made of leather).
• Bathe (or even to wash anything more than fingers; you may not use a deodorant--not even a spray type--since it is similar to washing).
• Have marital relations.
• Use cosmetics or body scents.

The Minor Fasts
The four minor fasts begin 72 minutes before local sunrise. They technically end at dark but functionally end after ma'ariv (and for the Fast of Esther, after hearing the megila). Unlike most times in the Jewish calendar, this 72 minutes is normal time and NOT based on the current length of the day (sha'a zmanit):

• Fast of Esther (Ta'anit Esther): Day preceding Purim (or sometimes earlier).
• Fast of Gedalia (Tzom Gedalia): Usually the day after Rosh Hashana.
• Tenth of Tevet (Asara b' Tevet):
• Seventeenth of Tamuz (Shiv'asar b'Tamuz): Beginning of the Three Weeks of semi-mourning beforeTish'a b'Av.

On all fast days, eating and drinking are forbidden. The Tenth of Tevet and the Seventeenth of Tamuz additionally have the same restrictions as the Nine Days. So you may wash or bathe on the Fast of Esther and on Tzom Gedalia but not on the Tenth of Tevet and the Seventeenth of Tamuz. (See Nine Days: Restrictions).
Note On a fast day that has been delayed for Shabbat, there may be leniencies for:

• The mohel, sandak, and father of a baby getting a brit mila to eat after mincha.
• Pregnant or nursing women (this leniency applies to eating throughout the day).

Fast for First Born
Fast for first-born males 13 years old and older, on the day before Passover. This includes first-born cohanim and Levites (levi'im). The fast begins 72 normal minutes before sunrise and ends with kiddush at the seder. However, the widespread custom is to attend a siyum on the day before the first seder so that the first-born men do not need to fast on that day.
 
Personal Fasts
Fast by a groom and bride on their wedding day is an example of personal fasts. This fast begins 72 normal minutes before sunrise and ends with drinking wine under the chuppa.

Jewish Festivals are listed in the Torah and are of two types: 

1. Three pilgrimage festivals (shalosh regalim):

• Passover,
• Shavuot, and
• Sukkot (including Shimini Atzeret).

These festivals were celebrated in ancient times by "appearing before God"--by bringing offerings to the Tabernacle or Temple.

2. High Holidays: 

• The Jewish New Year (Rosh Hashana—“Yom Teru'a” in the Torah), and the
• Day of Atonement (Yom Kippur).

 
Duration
Jewish holidays that were originally one day are now observed as follows:

• Rosh Hashana--2 days.
• Yom Kippur--1 day.
• Shavuot--1 day in Eretz Yisrael or 2 days elsewhere.
• Passover has festival days at the beginning and end of the holiday and intermediary days of lesser holiness, which are called chol ha'moed. In Eretz Yisrael, Passover lasts for 7 days in total and the first and last days are festival days. Outside of Eretz Yisrael, Passover lasts 8 days and has two festival days at the beginning and two at the end.
• Sukkot has festival days at the beginning and at the end and intermediary days of lesser holiness, which are called chol ha'moed. In Eretz Yisrael, Sukkot lasts for 8 days and the first and last days are festival days (the last day is Shimini Atzeret). Outside of Eretz Yisrael, Sukkot lasts for 9 days and the first two days and last days are festival days (the 8th day is Shimini Atzeret and the 9th day is Simchat Torah).

Character
Each holiday contributes its own character to Jewish life (Passover--the theme of freedom; Yom Kippur brings atonement, etc.). 

Celebrating
How to celebrate these holidays is detailed in our Oral Law and halacha books. Jewish festivals as practiced today are similar in holiness to Shabbat. As with Shabbat, the Jewish festival has candle lighting, kiddush at two meals, and havdala.   We eat our best food and wear our best clothing on Jewish festivals (we eat our next-best food and wear our next-best clothing on Shabbat!).
The main idea behind eating meals on Jewish festivals is joy (simcha), so you should drink wine and eat meat (only if you enjoy wine and meat).  There is no third meal on Jewish festivals since people used to eat two meals each day (adding a third meal on Shabbat was for enjoyment/oneg).
 
Melachot
Any activities or actions permitted on Shabbat are also permitted on the Jewish festivals. Actions that are forbidden on Shabbat are generally also forbidden on Jewish festivals, but there are some leniencies (only if the actions are needed for that festival day).
Examples

• Lighting from an existing flame,
• Cooking and baking for the Jewish festival day, and
• Carrying outside the eruv (hotza'a--transferring objects between domains).

 
Grama
Grama (indirectly causing an action) is permitted on Jewish festivals (but not on Shabbat). For example, you may advance or delay a timer that will make a light go on or off in the future (the timer must already be plugged in and operating from before sunset of the festival day).
Note For an action to be considered indirect based on time, there must be at least 2.5 seconds after the first action is done before the resulting action begins to happen.

Psik Reisha Dla Neicha Lei
Psik reisha dla neicha lei is forbidden on Jewish festivals, just as it is on Shabbat.

D'oraita Restrictions
D'oraita restrictions apply world-wide to:

• First and seventh days of Passover,
• First and eighth days of Sukkot,
• First day of Shavuot,
• Yom Kippur,
• First day of Rosh Hashana.

Note The same restrictions apply to all other Jewish festival days but are rabbinical.
 
Women
In general, women are not required to perform the positive, time-dependent commandments. Women and girls are not required to eat any Jewish festival meals except the Passover seder meal (but they are not allowed to fast on those days).

(from kashrus/kk-medi-terumos.htm">http://www.star-k.org/kashrus/kk-medi-terumos.htm, used with permission)

Post this document in a conspicuous place.

1. Break or cut off more than one hundredth of the food and set it aside (for teruma and terumat ma'aser).
2. Say the following (either in Hebrew or English):
   
   
   
   Yoteir me'echad me'me'a she'yeish kahn harei hu teruma gedola be'tzad tzefono. Oto echad me'me'a she'yeish kahn ve'od tish'a chalakim k'moto be'tzad tzefono shel ha'peirot harei hu ma'aser rishon. Oto echad me'me'a she'asitiv ma'aser rishon asuy terumat ma'aser, uma'aser sheini b'dromo, u'mechulal hu ve'chumsho al peruta be'matbei'a sh'yichidita lechilul ma'aser sheini ve'revai. Ve'im tzarich ma'aser ani ye'hei ma'aser ani bi'dromo. Im hu revai ye'hei mechulal hu ve'chumsho al peruta be'matbei'a she'yichidita le'chilul ma'aser sheini ve'revai.
   
   (Im ma'aser minim harbei tzarich le'hosif) “kol min al mino.”
   
   
   Translation
   (If there is a food of one type that requires separation) Whatever is MORE than one hundredth of this food shall be teruma on the north side of the piece that I have set aside. The one hundredth that is left in the piece I have set aside plus nine other pieces the same size on the north side of the food shall be ma'aser rishon. That same one hundredth in the piece I set aside that I have made ma'aser shall be terumat ma'aser.
   Furthermore, I am proclaiming ma'aser sheini to be in effect on the south side of the food, and I am redeeming it and its fifth on a pruta (smallest amount of money recognized by the Torah for most purposes) of this coin which I have in front of me. If this food needs ma'aser ani, the ma'aser ani shall take effect on the south side of the food.
   If this food is subject to the laws of neta revai then it and its fifth shall be redeemed on a pruta of this coin that I have in front of me.
   
   If there is a food of more than one type, add each type of food for its type.
    
3. Wrap the broken or cut-off piece in plastic and discard.
4. The coin--dime or coin of greater value--must eventually be disposed of in such a manner that it will not be used.
5. The food may now be eaten.

 
If you do not want to say the long version, you may say this shorter version, after having separated a piece larger than 1\% of the total food:
All separations and redemptions shall take effect as is specified in this Star-K document outlining the Procedure for Separating Terumot and Ma'asrot, Tithes and Redemptions, which I have in my possession.

Whether saying the long or short version, only a little over one hundredth of the food will not be permitted to eat; all the rest may be eaten. Even though the tithes constitute over one fifth of the food, one is permitted to eat most of the tithes oneself, even though he may not be a Cohen or a Levi. Under no circumstances will it suffice merely to break off a piece of the food and throw it away. The aforementioned instructions must be strictly followed. The laws of the tithes apply to everyone, including the Cohen and Levi.

You must say the blessing lehafrish trumot u'ma'asrot if you know the produce definitely needed to have teruma and ma'aser taken; it was definitely:

• Grown on Jewish-owned land in halachic Eretz Yisrael and
• Had not yet had teruma and ma'aser taken from it.

BUT you must not say the blessing if the produce might have:

• Not been grown on Jewish-owned land in halachic Eretz Yisrael, OR
• Already had teruma and ma'aser separated.

The International Dateline (IDL), which is 180 degrees away from Greenwich, England, crosses the Pacific ocean from north to south and divides a region of safek/doubt as to which day is Shabbat. This region's eastern boundary is a line 180 degrees east of Jerusalem, which lies between Hawaii and the US mainland; the western boundary is east of Shanghai. All countries in this region of IDL safek/doubt are island countries.
 
In a region of doubt, such as Tasmania, keep normal Shabbat (Shabbat d'rabanan) on local Saturday and keep Shabbat d'oraita on:

• West of mainland USA, but
• East of the IDL, and
• Not attached to the mainland.

• West of the IDL, but
• East of Shanghai, and
• Not attached to the mainland.

Note In all cases, you must still observe regular Shabbat on Friday night/Saturday.
Situation
You are in a place near the International Dateline (IDL) in which you are not sure which day of the week it is halachically: Shabbat or, if you are east or west of the IDL, Friday or Sunday.
What To Do
On the Friday or Sunday in question, there is no shvut (d'rabanan prohibitions, including muktza), so you may do all melacha d'rabanan WITHOUT a shinui. You may:

• Ask or tell a non-Jew to do anything, including a melacha d'rabanan or d'oraita.
• Ride in a cab or car driven by a non-Jew.

• Use electricity--except for heat or light—including turning on a fan or air conditioner (heat and light are forbidden by the Torah).
• Use the telephone. (Using a cellphone may be permissible--ask a rabbi).

• Carry from a private domain (reshut ha'yachid) to another private domain, even through a public domain (reshut ha'rabim); but you may not stop walking in the public domain and you may not put the object down in the public domain unless you use a shinui.
• There is no practical way to light candles, even using a shinui, but a non-Jew may light them for you and and you may say the blessing on the candles.
• Swim, surf, scuba dive, climb, and play all games that do not use melacha. You may not wring out clothes and if you are swimming or scuba diving, your swimsuit or wetsuit must be clean.
• Walk any distance (there is no techum Shabbat d'oraita).
• Kinyan. You may acquire items.

• Fly, including check in and getting on plane if:
  • The pilot is non-Jewish, and
  • You don't do any melacha d'oraita (including any writing) without a shinui.
• Use a computer if it automatically goes to sleep after less than 24 hours of not being used.
• Shower. However:
  • You may not use an “instant on” hot water system in which the water is heated as you use it; you may only use the hot water if it has a holding tank.
  • You may use only liquid soap; hard soap is forbidden.
• Ingest medicine (but you may not smear it on skin).
• Use some make up, such as rouge, mascara, eye shadow. You may not use lipstick.
• Open a refrigerator with light (and all other psik reisha d'la neicha lei).

• You may buy necessities on Friday or Sunday as long as:
  • The store owner is not Jewish (or if he/she is Jewish, does not write or print a receipt),
  • You do not write, and
  • There is no reshut ha'rabim.

You may also do melacha d'oraita if:

• You use a shinui (non-normal way of doing that action--this is forbidden d'rabanan on Shabbat but is allowed on the Friday or Sunday in question), OR
• Two or more people do the melacha together.

 
D'oraita, you may not:

• Cook food.

• Turn on lights (but you may turn them off).
• Carry from domains.
• Boneh – building any permanent structure.
• Write two or more letters of the alphabet.
• Drive--there is no practical way to drive using a shinui.
• Shave--there is no practical way to shave using a shinui.
• Use toothpaste (but you may use tooth-cleaning powder).
• Use skin cream--you may dab it on without smearing it.

However, you may do these following actions with a shinui on the Friday or Sunday in question, as follows:

• Cook food. You must put food in the cooking utensil first, then turn on the heat with shinui. You may turn off the heat even without a shinui.
• Turn on lights (such as with your elbow).
• Stop along the way when carrying from a private domain (reshut ha'yachid) to another private domain, even through a public domain (reshut ha'rabim). As a shinui, you may carry the object in your mouth (as long as it is not food), etc.

Note Carrying something in your pocket is NOT a shinui.

• Tear paper (such as putting toilet paper across knees and moving the knees apart).
• Write (such as with the opposite hand).

Flying East From Australia on Sunday If You Cross IDL from Friday into Saturday

To pray for a sick person, say the yehi ratzon inserted into the refa'einu (8th) paragraph of the amida on weekdays (but not on Shabbat or Jewish festivals) either:

• When saying the amida (add your request after "makoteinu"), or
• After reciting Tehilim (Psalms) for the sick person (see Concluding Tehilim with Yehi Ratzon of Refa'einu).

If you say Psalms/tehilim for a sick person, you should conclude with the yehi ratzon that is sometimes added in shemoneh esrei in refa'einu.