SEV Biblia, Chapter 17:12 Y de edad de ocho días será circuncidado en vosotros todo macho por vuestras generaciones: el nacido en casa, y el comprado a dinero de cualquier extranjero, que no fuere de tu simiente.
Clarke's Bible Commentary - Genesis 17:12 Verse 12. He that is eight days old] Because previously to this they were considered unclean, Lev. xii. 2, 3, and circumcision was ever understood as a consecration of the person to God. Neither calf, lamb, nor kid, was offered to God till it was eight days old for the same reason, Lev. xxii. 27.
Matthew Henry Commentary Verses 7-14 - The covenant of grace is from everlasting in the counsels of it, and to everlasting in the consequences of it. The token of the covenant wa circumcision. It is here said to be the covenant which Abraham and his seed must keep. Those who will have the Lord to be to them a God, mus resolve to be to him a people. Not only Abraham and Isaac, and his posterity by Isaac, were to be circumcised, but also Ishmael and the bond-servants. It sealed not only the covenant of the land of Canaan to Isaac's posterity, but of heaven, through Christ, to the whole churc of God. The outward sign is for the visible church; the inward seal of the Spirit is peculiar to those whom God knows to be believers, and he alone can know them. The religious observance of this institution wa required, under a very severe penalty. It is dangerous to make light of Divine institutions, and to live in the neglect of them. The covenan in question was one that involved great blessings for the world in all future ages. Even the blessedness of Abraham himself, and all the rewards conferred upon him, were for Christ's sake. Abraham wa justified, as we have seen, not by his own righteousness, but by fait in the promised Messiah.
Original Hebrew ובן 1121 שׁמנת 8083 ימים 3117 ימול 4135 לכם כל 3605 זכר 2145 לדרתיכם 1755 יליד 3211 בית 1004 ומקנת 4736 כסף 3701 מכל 3605 בן 1121 נכר 5236 אשׁר 834 לא 3808 מזרעך 2233 הוא׃ 1931