“For no one is a Jew who is merely one outwardly, nor is circumcision outward and physical. But a Jew is one inwardly, and circumcision is a matter of the heart, by the Spirit, not be the letter. His praise is not from man but from God” (Romans 2:28-29, ESV).
No subject was more stressed in the teaching of Jesus than the need for inner conformance to the will and nature of God. From the lessons of the Sermon on the Mount to those of the last week before his death on the cross, the Lord continually emphasized that service to God requires commitment from the inner person as well as obedience to outward, physically oriented commands. His mandate, “You therefore must be perfect, as your heavenly Father is perfect” (Matthew 5:48), is best understood as demanding complete obedience, within and without, to God’s will.
Paul, in Romans, explores the definition of “Jew.” By this ethnic description he means “People of God.” His question may be phrased, “Who are the real people of God?” He goes on to show that the answer is not, as many of his kinsmen would have claimed, the descendants of Abraham through the flesh (Romans 2:28; 4:9-15; 9:7-8). Rather, those who share the faith of Abraham are his true descendants and constitute the true People of God.
Physical circumcision was a mark or sign of God’s covenant with Abraham, to be practiced by every male among his descendants (Genesis 17:9-14). But in Christ this covenant was fulfilled, became obsolete, and was abolished (Hebrews 8:7-13). In place of the older fleshly seal of circumcision there now is given a more spiritual mark, the “circumcision of the heart” (Romans 2:29).
That circumcision is performed through the Spirit of God (Romans 2:29), not in some miraculous or subjective manner, but through “the renewing of the mind” (Romans 12:2) or the implanting of God’s word (James 1:21).
When one hears God’s message, studies his inspired Word (the Bible), and seeks to obey it, his heart is transformed to become more like God and Christ (Titus 2:11-14). This is what is sometimes referred to as spiritual circumcision. When one’s heart (inner self, spirit) takes on the nature of Christ, then his life will be guided by and reflect that nature.
This is not just poetic language or some ideal picture of the Christian life. It is absolutely essential.
“For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. For to set the mind on the flesh is death, but to set them mind on the Spirit is life and peace. For the mind that is set on the flesh is hostile to God, for it does not submit to God’s law, indeed, it cannot. Those who are in the flesh cannot please God” (Romans 8:5-8).
As I have written before in these articles, “heart” and “mind” are often used synonymously in Scripture. To be circumcised in the heart is exactly the same as being renewed in the mind. No one whose mind or heart has not become attuned to God’s will can claim to be part of his people, regardless of his genealogy or physical acts of obedience.
Abraham’s descendants are those with true faith in God, those who follow him in obedient trust. Further, they are those whose heart testifies to their possession of the spirit of Christ (Romans 8:9-10). Unless our spirit (that is our nature or character) has become like that of Jesus, we do not belong to him, nor do we have hope of eternal life. It is indeed a matter of the heart.