By: Rabbi Eliyahu Tobal

1.      Obligation to Thank Gd for Food
One is obligated to recite Birkat Hamazon (grace after meals) if he ate a kezayit (approximately 30 grams) of bread according to rabbinic enactment. The source for this missva is the verse in Devarim (8:10), “… and you shall eat and be satiated, and you shall bless Hashem your Gd for the good land he has given you.”
This obligation applies to both men and women (though some authorities maintain that women are obligated only by force of rabbinic enactment).
2.         Requirement of a Formal Blessing
The Torah obligation requires simply thanking Hashem for one’s food, but the Prophets required the recitation of a fixed text. Moshe Rabbenu composed the first blessing of Birkat Hamazon when the Jews traveled in the desert, and Yehoshua composed the second when they entered the Land of Israel. Later, David Hamelech and Shelomo Hamelech composed the third blessing. The fourth was composed by the Anshei Keneset Hagedolah (Men of the Great Assembly) when the Roman government authorized the burial of the victims of the Betar massacres. The supplications recited after the fourth blessing were also established by the Anshei Keneset Hagedolah.
3.         Expressing Gratitude with Feeling
Imagine the gratitude a heart attack survivor would feel to the bystander who administered CPR and saved his life. Common decency would dictate thanking that individual with heartfelt sincerity.
This is precisely the debt of gratitude we owe to the Almighty every time we eat or drink. We could not survive without food and drink, and each time Hashem provides our sustenance He is truly saving our lives, for which we must feel truly indebted.
Therefore, one should recite Birkat Hamazon with sincere feelings of joy and gratitude to the Almighty for sustaining us. One who is thankful and appreciative is certainly worthy of continued blessing. If one does not recite the required berachot before and after eating, a prosecuting angel comes before Gd and charges that this individual is undeserving of continued blessing.
4.   Using Hebrew or Understanding the Text
It is preferable to recite Birkat Hamazon in Hebrew. If one cannot read Hebrew, one should try to use a transliterated text to pronounce the Hebrew words of the blessing. Even if one does not understand Hebrew, this is preferred. If however, one cannot read Hebrew or find a transliterated text, he/she may recite a translation of the blessing in any language provided that what is being read is understood. If one recited the blessing in a language other than Hebrew and did not understand what he/she read, the obligation was not fulfilled and the blessing must be repeated.
  1. Blessing in an Audible Tone
One should preferably recite Birkat Hamazon audibly, such that he/she could hear the recitation. One who recited Birkat Hamazon inaudibly has nevertheless fulfilled his/her obligation, provided that his/her lips were moving while reciting the words. One who did not recite the words with his/her lips must repeat Birkat Hamazon.
As with all berachot, when recited in the presence of other Jewish people, one has the additional obligation to say the blessing loud enough so that those present could hear it and answer amen.
  1. Conduct During Birkat Hamazon
One should say Birkat Hamazon in the place where he/she ate, while seated, and from a siddur. One who does not have a siddur and knows Birkat Hamazon by heart should recite it with his/her eyes closed. One should not point or motion throughout the recitation of Birkat Hamazon and should recite the blessing with the same sense of awe required while reciting the Amida prayer.
·         It is proper to leave a piece of bread on the table while reciting Birkat Hamazon. If no bread remained after the meal, one should place a different piece on the table. However, one should not bring out a new loaf of bread.
·         According to Kabbalistic teaching, one should leave the leftovers of one’s meal on the table during Birkat Hamazon.
·         Before Birkat Hamazon, one should remove all knives and empty utensils from the table.
  1. Reciting the Blessing in the Proper Time Frame
One may recite Birkat Hamazon until the point when his food is completely digested, which is a minimum of 72 minutes or longer if one still feels satiated. If one cannot ascertain whether or not the digestion has completed, he should eat another kezayit of bread and then recite Birkat Hamazon. If this is not possible, he should not recite Birkat Hamazon.
If a person participates in a meal that extends over several hours, he should preferably make a point to eat occasionally, so that an extended period does not pass between eating and Birkat Hamazon. Alternatively, he may eat a kezayit of bread right before reciting Birkat Hamazon.
  1. Blessing in Situations of Uncertainty
If a man is unsure whether he recited Birkat Hamazon, he should recite the first three blessings (until “Boneh Yerushalayim”). A woman in such a case does not recite Birkat Hamazon at all.
If one ate between 29-58 grams of bread and does not remember if he recited Birkat Hamazon, then he does not recite it. If he is unsure whether he ate more or less than 58 grams and cannot remember whether he recited Birkat Hamazon, then he does not recite it.
It is proper not to get involved in any other activity after eating until one recites Birkat Hamazon.
  1. Reciting the Blessing in the Proper Place
Birkat Hamazon must be recited in the place where one ate. However, if one recited Birkat Hamazon elsewhere, he does not repeat it.
One who ate bread may not leave that room before reciting Birkat Hamazon unless this becomes necessary. Some authorities permit leaving the room if one can still see the place where he ate.
If one mistakenly left the room without reciting Birkat Hamazon, he must return to the room and recite Birkat Hamazon. If he had traveled a long distance and will miss the final time for Birkat Hamazon by the time he returns, then he should recite the blessing in his current location.
  1. Insertions for Special Occasions
On Shabbat, one adds to Birkat Hamazon the paragraph of “resseh vehahalissenu.” One who forgot to add this prayer on Shabbat, during Friday night or Shabbat lunch, must repeat Birkat Hamazon. If he realizes his mistake before reciting the words “HaKel Avinu,” then he should recite, “Baruch ata Hashem Elokenu melech ha’olam shenatan Shabbat lemenuha le’amo Yisrael” and then begin anew the blessing of “HaKel Avinu.”
On Rosh Hodesh and holidays one adds the “ya’aleh veyavo” prayer to Birkat Hamazon. One who forgot to add this prayer does not repeat Birkat Hamazon, except on the first night of Pesah or the first night of Sukkot. If one realizes his mistake before “HaKel Avinu,” he may recite, without Hashem’s name, “Baruch shenatan yamim tovim le’amo Yisrael.”