In the selfsame day was Abraham circumcised, and Ishmael his son.

Matthew Henry's Concise Commentary

17:23-27 Abraham and all his family were circumcised; so receiving the token of the covenant, and distinguishing themselves from other families that had no part nor lot in the matter. It was an implicit obedience; he did as God said unto him, and did not ask why or wherefore. He did it because God bade him. It was a speedy obedience; in the self-same day. Sincere obedience makes no delay. Not only the doctrines of revelation, but the seals of God's covenant, remind us that we are guilty, polluted sinners. They show us our need of the blood of atonement; they point to the promised Saviour, and teach us to exercise faith in him. They show us that without regeneration, and sanctification by his Spirit, and the mortification of our corrupt and carnal inclinations, we cannot be in covenant with God. But let us remember that the true circumcision is that of the heart, by the Spirit, Ro 2:28,29. Both under the old and new dispensation, many have had the outward profession, and the outward seal, who were never sealed by the Holy Spirit of promise.

Matthew Henry's Whole Bible Commentary

Verses 23-27

We have here Abraham's obedience to the law of circumcision. He himself and all his family were circumcised, so receiving the token of the covenant and distinguishing themselves from other families, that had no part nor lot in the matter. 1. It was an implicit obedience: He did as God had said to him, and did not ask why or wherefore. God's will was not only a law to him, but a reason; he did it because God told him. 2. It was a speedy obedience: In the self-same day, v. 23, 26. Sincere obedience is not dilatory, Ps. 119:60. While the command is yet sounding in our ears, and the sense of duty is fresh, it is good to apply ourselves to it immediately, lest we deceive ourselves by putting it off to a more convenient season. 3. It was a universal obedience: He did not circumcise his family and excuse himself, but set them an example; nor did he take the comfort of the seal of the covenant to himself only, but desired that all his might share with him in it. This is a good example to masters of families; they and their houses must serve the Lord. Though God's covenant was not established with Ishmael, yet he was circumcised; for children of believing parents, as such, have a right to the privileges of the visible church, and the seals of the covenant, whatever they may prove afterwards. Ishmael is blessed, and therefore circumcised. 4. Abraham did this though much might be objected against it. Though circumcision was painful,-though to grown men it was shameful,-though, while they were sore and unfit for action, their enemies might take advantage against them, as Simeon and Levi did against the Shechemites,-though Abraham was ninety-nine years old, and had been justified and accepted of God long since,-though so strange a thing done religiously might be turned to his reproach by the Canaanite and the Perizzite that dwelt then in the land,-yet God's command was sufficient to answer these and a thousand such objection: what God requires we must do, not conferring with flesh and blood.