“Abraham took Ishmael his son, and all those born in his house, and all those purchased with his money, every male among the people of Abraham’s household, and he circumcised the flesh of their foreskin on that very day, as God had spoken with him” (Genesis 17:23). “Abraham took Ishmael his son, and all those born in his house” – Rabbi Aivu said: When Abraham circumcised [the foreskins of] all those born in his house, he stacked them into a mound of foreskins.
When the sun shone upon them, they became wormy,28They began to rot. and their odor rose before the Holy One blessed be He like the incense of the spices, and like a burnt offering that is given over completely into the [altar’s] fire.29And is referred to as “a pleasing aroma to the Lord” (Exodus 29:41). The Holy One blessed be He said: ‘When the descendants of this man will come to commit transgressions and evil deeds, I will remember this aroma and become filled with mercy for them, and I will take pity on them.’