<b>And Abraham took another wife (Gen. 25:1).</b> May our master teach us: How many times should one pray each day? R. Samuel the son of Nahman declared: Since there are three periods in each day, a man should pray three times every day—in the morning, when the sun is in the east; at noon, when the sun is at its zenith; and in the afternoon, when the sun is in the west. R. Joshua the son of Levi stated: Abraham established the morning prayer, as it is said: <i>And Abraham arose early in the morning</i> (Gen. 22:3); Isaac instituted the afternoon prayer, as it is said: <i>And Isaac went out to meditate in the field at eventide</i> (ibid. 24:63); and Jacob introduced the evening prayer, as it is said: <i>And he lighted upon the place and tarried there all night because the sun was setting</i> (ibid. 28:1).
When R. Akiba prayed with the congregation, he did so in the usual way, but when he prayed by himself, one would leave him standing in one corner (of the room) only to find him in another corner as a consequence of his kneeling and prostrating himself.
Why were prayers instituted three time a day? It was so that a man might add to this (minimal) number of prayers. The same goes for the commandments of Torah study and producing children. For the Torah teaches that if a man’s wife dies, he should remarry and produce additional children. You know this to be so from the fact that after Abraham’s wife died, he did not live alone. He remarried, as it is said: <i>And Abraham took another wife</i>.