"Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill.” (Mt 5:17)
The theologian Karl Rahner wrote of “anonymous Christians” whose lives of faithful searching for truth and authentic goodness open for them the doors of the kingdom without their having explicitly acknowledged God or even heard the name of Jesus. Are we Christians then anonymous Israelites and followers of the Law without keeping it literally? The call of the Gentiles was interpreted by the early Church to mean that keeping all the precepts of the Law was not necessary for salvation in Christ. Paul said, daringly: “we are the circumcision, we who worship through the Spirit of God, who boast in Christ Jesus and do not put our confidence in flesh” (Phil 3:3). He could equally have said, “we are the Law” – written no longer on tablets of stone or on pieces of paper attached to doorframes and hands and foreheads, but on the heart, as Jeremiah dreamed:
“This is the covenant that I will make with the house of Israel after those days, says the Lord: I will put my law within them, and I will write it on their hearts; and I will be their God, and they shall be my people.” (Jer 31:33)
“When Gentiles, who do not possess the law, do instinctively what the law requires, these, though not having the law, are a law to themselves. They show that what the law requires is written on their hearts, to which their own conscience also bears witness; and their conflicting thoughts will accuse or perhaps excuse them on the day when, according to my gospel, God, through Jesus Christ, will judge the secret thoughts of all.” (Rom 2:14-16)
As Paul is at pains to point out, this being “a law to themselves” does not mean moral relativism or license to sin, but a gift of conscience given to all without partiality. This could also be called the thoughts of God (Cf. Is 55:8) or the “mind of Christ” (1 Cor 2:16).
The Law written on the heart gives emphasis not to the external form only (the Pharisaic preoccupation with straining out gnats) but to the inner principles. Hence Jesus’ comments regarding the laws against murder and adultery call for transformation of the heart. Long before the point of taking a life or someone else’s wife is reached, there are interior movements and choices for which we are responsible.
Why is it that we and the Pharisees are so much more comfortable with rigid laws focused on external matters? Why do we feel disconcerted by the radical demands Jesus makes in this gospel? Perhaps it is because conformity to external norms gives us a sense of security and control over our lives and the way people see us. A call to inner transformation leaves us with no quarter to ourselves. The bright light that Jesus shines on the human heart lays bare what is hidden in dark and dusty corners:
“For it is from within, from the human heart, that evil intentions come: fornication, theft, murder, adultery, avarice, wickedness, deceit, licentiousness, envy, slander, pride, folly. All these evil things come from within, and they defile a person.” (Mk 7:21-23)
The angry thought and the look of desire defile us before God. The monastic tradition teaches that we do not have complete control over the thoughts that arise in our hearts, but we do have a choice as to whether such thoughts linger long enough to gain strength and influence our conduct. Our goal, according to John Cassian, is to grow in purity of heart. This means that we do not allow ourselves to be a harborage for pests, such as illicit desire and anger, which lead us to use and abuse others for our own satisfaction and aggrandizement. Rather, we seek to be filled with the thoughts of God, the mind of Christ:
“The fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control; against such things there is no law.” (Gal: 22-23)