257. Starting Hilchos Tefillah

Kriyas Shema 4:8

Ritually impure people are obligated to recite the Shema with the brachos before and after it. This is so even if it is possible for them to purify themselves that same day. Ezra and his court instituted that a man who has had a seminal emission was not allowed to read words of Torah until he immersed in a mikvah, rendering such a person different from other ritually impure people. This rule was never universally accepted. Most people were not able to observe it, so it was nullified. Instead, the Jewish people accepted the practice to read the Torah and recite Shema even after a seminal emission; this is because words of Torah are incapable of being rendered ritually impurity. Instead, they retain their purity forever as per Jeremiah 23:29, “‘Are my words not like fire?’ says Hashem.” Just as fire cannot be rendered ritually impure, neither can words of Torah.

Tefillah u’Birkas Kohanim 1:1

There is a mitzvah to pray every day, as per Exodus 23:25, “You shall serve Hashem, your God.” We have a tradition that this service is prayer as per Deuteronomy 11:13, “Serve Him with all your heart.” Our Sages explained that service of the heart refers to prayer. The Torah does not prescribe a particular number of prayers or a specific text, nor does the Torah set particular times for prayer.