Summary: Jesus came not to destroy the law, but to keep and fulfill it. We also are required to be obedient to the law - not indeed as a means of salvation (which it could never be) - but as an expression of our love and service.
THE KEY TO RIGHTEOUS LIVING
I. Jesus’ statement is emphatic:- “Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfill” (Matthew 5:17).
The righteousness of God is the Lord Jesus Christ. He is the end of the law, the one to whom the law points and who fulfills the law within Himself (cf. Romans 10:4).
By saying this, He is not abrogating the Old Testament: for it was to these writings that he turned in His recent wilderness struggles with the devil (Matthew 4:4-10).
II. He continues:- “Till heaven and earth pass away,” not one iota, not one dot “shall pass from the law, till all is fulfilled” (Matthew 5:18).
What we have already learned about God in the Old Testament still stands, but comes to greater clarity in the Person of our Lord Jesus Christ.
The types and prophecies reach their fulfillment in Him. Thus He says (in case we missed it), “I am come” (Matthew 5:17)!
III. Jesus’ attitude to the law is summed up in His instruction to His disciples (Matthew 5:19). We are saved by grace, yes - but we are not free to disobey what God commands. Yet there are those, even in the church, who do just that - and teach others so.
IV. Indeed, the disciples are warned that their righteousness must exceed that of the scribes and Pharisees (Matthew 5:20). This too is emphatic. Mere outward conformity will never suffice (1 Samuel 15:22).
Elsewhere, Jesus instructs His followers to obey the scribes and Pharisees, for they sit in Moses’ seat - but don’t do as they do (Matthew 23:2-3)! The law still has status in the Christian life - not indeed as a means of salvation, for that it never could be. The difference for us is that we have the indwelling of the Holy Spirit (Ezekiel 36:27) - and thereby the law is now ‘written upon our hearts’ (Jeremiah 31:33).
Christian morality is more than keeping a set of rules and regulations. The Christian character is shaped by our relationship with Jesus, our continual supping with Him in word and sacrament, prayer and devotion (Matthew 5:6). Having been made righteous with the righteousness of Christ (2 Corinthians 5:21), we are thus empowered to be salt and light in the world (Matthew 5:13-16) - and to show forth His righteousness in ours.