The 19th mitzvah is that we are commanded to thank G‑d (exalted be He) after each time we eat.1

The source of this commandment is G‑d's statement,2 "When you have eaten and are satiated, You shall bless G‑d your L‑rd."

The Tosefta3 says, "Reciting the blessing after eating is a mitzvah of the Torah, as the verse says, 'When you have eaten and are satiated, you shall bless G‑d your L‑rd.' "

The details of this mitzvah are explained in many places in the tractate Berachos.4