Citation sur La Genèse 17:2

I will establish My covenant between Me and thee. He was not aware which part of his body was to be circumcised. And so the Holy One, blessed be He, indicated the place of circumcision when he said; And I will make thee exceedingly fruitful. That is to say, at the place through which you increase and multiply you are to be circumcised. However, Bar Kappara was of the opinion that Abraham decided upon the place of circumcision by analogy. He said to himself: “Which part of a tree is subject to the law of orlah?²⁴Orlah is the law requiring circumcision discussed in the mishnaic tractate of that name. It is that part of the tree which produces fruit, and so I must be circumcised at the place from which I will produce my fruit.”