The first was separation from his kindred and country at the Divine command. The call of Abraham is typical of that call of the Holy Spirit, which sooner or later comes to every sinner, to turn away from all known sin as a preparation for saving faith in Christ.
The second point of transition in Abraham's life was his justification by faith. He believed in Jehovah; and He counted it to him for righteousness. St. Paul cites this as a conspicuous instance of justification by faith under the old covenant. Abraham had exercised faith in obeying the call to separation; but it was what theologians style prevenient rather than saving faith.
Twenty-four years after Abraham's first call, and several years after his justification, he passed the third and final transition in his religious career, which in modern parlance would be called his spiritual perfection. When he was ninety years old and nine (Gen xvii.1) Jehovah disclosed to him His almightiness under the name of El-Shaddai, Almighty God, as the ground of a new commandment, "Be thou perfect."
With this injunction was the institution of circumcision as necessary to the perfection required, demonstrating typically that spiritual circumcision or entire sanctification is the gateway into Christian perfection, or pure love, styled by John "perfect love" which "casteth out" all "tormenting fear." For in "the self-same day" in which Abraham was commanded to walk before God and be perfect, he submitted to the painful rite of circumcision, the removal, in Hebrew conception, of that bodily impurity with which he was born. Here we find a striking type of original or birth sin, denied by all the self-styled modern liberalists, put away by "the circumcision of Christ" through the agency of the sanctifying Spirit, not by a gradual outgoing of native depravity, but by the heroic treatment of instantaneous excision. Hence the doctrine of spiritual circumcision is a two-edged sword, cutting away Pelagianism with one edge and gradualism with the other. The first is the denial of inbred or birth sin, and the second is the denial of its instantaneous extinction when faith lays hold of Him who "is able to save unto the uttermost."
Some persons may insist that there was a fourth crisis in the life of the father of the faithful — the supreme test of his faith in obeying the command to offer up Isaac. It was a crisis, but not a transition from one state of grace to another. God found Abraham perfect in loyalty and love, and demonstrated this fact to all the coming generations of Bible-readers. The three marked epochs in his life were his separation, his justification, and his entire sanctification, the beginning of his perfect walk before Jehovah and not before misjudging mortals.
— Mile-Stone Papers, Part 1, Chapter 5.