Yevamot

teaches that the Divine Presence does not rest on less than two thousand and two myriads of Israelites.  Should the number of Israelites happen to be two thousand and two myriads less one, and any particular person has not engaged in the propagation of the race, does he not thereby cause the Divine Presence to depart From Israel! Abba Hanan said in the name of R. Eliezer: He deserves the penalty of death; for it is said, And they had no children,  but if they had children they would not have died. Others say: He causes the Divine Presence to depart from Israel; for it is said, To be a God unto thee and to thy seed after thee;  where there exists 'seed after thee' the Divine Presence dwells [among them]; but where no 'seed after thee' exists, among whom should it dwell! Among the trees  or among the stones? MISHNAH. IF A MAN TOOK A WIFE AND LIVED WITH HER FOR TEN YEARS AND SHE BORE NO CHILD, HE MAY NOT ABSTAIN [ANY LONGER FROM THE DUTY OF PROPAGATION].  IF HE DIVORCED HER SHE IS PERMITTED TO MARRY ANOTHER, AND THE SECOND HUSBAND MAY ALSO LIVE WITH HER [NO MORE THAN] TEN YEARS.  IF SHE MISCARRIED [THE PERIOD OF TEN YEARS] IS RECKONED FROM THE TIME OF HER MISCARRIAGE. GEMARA. Our Rabbis taught: If a man took a wife and lived with her for ten years and she bore no child, he shall divorce her and give her her kethubah,  since it is possible that it was he who was unworthy to have children from her.  Although there is no definite proof for this statement  there is nevertheless a [Scriptural] allusion to it: After Abram had dwelt ten years in the land of Canaan.  This  teaches you that the years of his stay outside the Land  were not included in the number.  Hence, if the man or the woman was ill, or if both were in prison, [these years] are not included in the number. Said Raba to R. Nahman: Let deduction be made from Isaac, concerning whom it is written, And Isaac was forty years old when he took Rebecca etc.  and it is also written, And Isaac was threescore years old when she bore them!  — The other replied: Isaac was barren.  If so,  Abraham also was barren!  — That text  is required For a deduction in accordance with the statement of R. Hiyya b. Abba. For R. Hiyya b. Abba stated in the name of R. Johanan: Why were the years of Ishmael counted? In order to determine thereby the years of Jacob. R. Isaac stated: Our father Isaac was barren; for it is said, And Isaac entreated the Lord opposite  his wife.  It does not say 'for his wife' but opposite. This teaches that both were barren.  If so, And the Lord let Himself be entreated of him  should have read, And the Lord let Himself be entreated of them!  — Because the prayer of a righteous man the son of a righteous man is not like the prayer of a righteous man the son of a wicked man. R. Isaac stated: Why were our ancestors barren? — Because the Holy One, blessed be He, longs to hear the prayer of the righteous. R. Isaac further stated: Why is the prayer of the righteous compared to a pitchfork?  As a pitchfork turns the sheaves of grain from one position to another, so does the prayer of the righteous turn the dispensations of the Holy One, blessed be He, from the attribute of anger to the attribute of mercy. R. Ammi stated: Abraham and Sarah were originally of doubtful sex;  for it is said, Look unto to the rock