⁵ But he is a Jew, who is one inwardly; and the circumcision is that of the heart, by the Spirit, and not by the letter .. but from God. Here Paul tells us that we must experience the circumcision of the heart, performed by the Holy Spirit, not by reading about Jesus and his commands, but by remaining in the spirit to receive his changing grace. This is done by silently listening, hearing, and obeying the teachings and commands heard from within your heart. For if you live according to the flesh you will die; but if by the Spirit you put to death the deeds of the body, you will live. Rom 8:13. Further, so kill (deaden, deprive of power) the evil desire lurking in your members: sexual vice, impurity, sensual appetites, unholy desires, and all greed and covetousness, for that is idolatry. Col 3:5. Further, By mercy and love, truth and fidelity, iniquity is purged out of the heart. Pro 16:6. And purge out therefore the old leaven, that you may be a new lump. 1 Cor 5:7. You must go to him. You must wait on him — listen silently, with the humility of a sinner in need of his changing power — grace. So we go to God and sit in humble silence to wait on Him, as we watch, listen, hear, obey... wait, watch, listen, hear, obey..... seek, listen, obey. You must endure to the end, when Christ brings salvation.

Isaac Penington speaks of experiencing the circumcision of his heart in his writing, The Holy Truth Defended:

"For we are the circumcision, which worship God in the Spirit, and rejoice in Christ Jesus, and have no confidence in the flesh." It is a precious thing to witness this scripture fulfilled in the heart; to experience that there, which inwardly circumcises, which cuts off the foreskin of the heart, which lies over it and veils it, until it is cut off by the inward appearance of the life and power of the Lord Jesus Christ inwardly revealed. Then when this is done, I can truly and sensibly say, I am a Jew inward. How so? How can that is proved? Why, I am inwardly circumcised. I have felt that within which circumcises the heart, and have borne the inward pain and cutting thereof, and am circumcised by it. That which stood between me and the Lord is cut off, the veil has been taken away, my stiff-necked and rebellious nature to God removed, the wall of separation is inwardly broken down, and now I am in true unity of Spirit and communion with my God, even with the Father, and the Son, in that One Holy Spirit by which they are One.

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