The Promise

Hashem promises Avraham that his children will be numerous/become many nations and that they will inherit the land. The question now is why did Avraham deserve this reward and why was the promise repeated many times throughout Avraham's life?

Avraham was the first person in the history of the world to recognize Hashem as the true creator and sustainer of the universe and to succeed in spreading ethical monotheism. He began to speculate about the existence of G-d at a young age. According to the Midrash, Avraham was imprisoned for his beliefs and thrown into a fiery pit. He was later miraculously released by the king. Afterwards, G-d commanded him to leave his home, his birthplace, and the house of his father to follow G-d to an unnamed land. He willingly did so. He brought his wife, nephew, and all of their possessions with him. He then proceeded to spread his practice of ethical monotheism throughout the land. It was then that Hashem first gave him the promise of זרע and ארץ. Avraham then built a מזבח for Hashem. Then came the famine. Avraham, Sara, and Lot went to Egypt for food. Avraham told Sara to lie and tell the Egyptians that she was Avraham's sister, not wife. He probably did this for two reasons. First of all, he didn't want to be killed so that the Egyptians could take his wife. Secondly, the promise of זרע required Avraham's wife. We know now that זרע refers to the descendants of Avraham and Sara. Without her, the promise might have been void. Hashem afflicts Pharaoh's house and the three of them return to Canaan. Then, Lot became corrupted. He decided that instead of following the ways of ethical monotheism, he would follow the ways of the people of Egypt: corruption and immorality. He decided to move to Sedom, a city as corrupt as Egypt. It was then that Hashem repeated the promise to Avraham.

Throughout Avraham's lifetime, Hashem repeated the promise when the validity of the promise was in doubt. Here, the problem appeared in the promise of זרע. At this point, Avraham was over age seventy five, and it seemed very unlikely that he would ever have children of his own. Therefore, he believed that the promise of children would come through Lot. When Lot strayed from the path of morality, Avraham considered that the promise was void. Therefore it was necessary for Hashem to renew the promise and to prove to Avraham that he would have numerous descendants and that those children would inherit the land of Canaan.