Deuteronomio 8:10

When thou hast eaten and art full, then thou shalt bless the Lord thy God. "From this place the Jews have made it a general rule, or, as they call it, an affirmative precept, that every one bless God at their meals, that is, give him thanks for his benefits; for he blesses us when he bestows good things on us, and we bless him when we thankfully acknowledge his goodness therein" (Patrick).