Is Saying the Shema an Obligation from the Torah?

Part 1: Rashi’s explanation of the Babylonian debate is inconsistent.

Part 2: The two Talmuds answer differently.

Part 3: The Rif says you can’t pray an extra Musaph prayer. Do you need to stand or lie down when you say the Shema, depending on the time of day?

Part 4: The Gra says that the Talmud twists the mishnah to conform to a particular rabbi’s school of thought. But it’s not done arbitrarily. Why rabbis disagree on the identification of the 613

Part 5: A review with questions and answers. The original practice, according to the Jerusalem Talmud, was to say the evening Shema at your bedside, not before the amidah.

Part 1
Part 2
Part 3
Part 4
Part 5