Our Lord’s Sermon on the Mount was His manifesto which paralleled Moses giving the Law on Mount Sinai. In it we are given God’s requirements for us in living this Christian life. We are called to be Holy as God is Holy. We are called to be Right in our actions as God is, which is Righteousness. Only those who are in Christ, with Christ in them, are able to do this although in a much diminished form from that of God Himself.
6 For all of us have become like one who is unclean,
And all our righteous deeds are like a filthy garment;
And all of us wither like a leaf,
And our iniquities, like the wind, take us away. Isaiah 64:6 (NASB)
What is our Lord’s number one desire for His sheep? Some would say that Jesus Christ wants Christians to just get along. Others might say that He wants Christians to live sacrificially while being busy doing good works. Some may say that proper religiosity is most important. The number one desire our Lord has for His people is that their Righteousness surpasses that of the Scribes and Pharisee so that their lives will bring Him glory.
17 “Do not think that I came to abolish the Law or the Prophets; I did not come to abolish but to fulfill. 18 For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished. 19 Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven.
20 “For I say to you that unless your righteousness surpasses that of the scribes and Pharisees, you will not enter the kingdom of heaven. Matthew 5:17-20 (NASB)
Our Lord’s Sermon on the Mount was His manifesto which paralleled Moses giving the Law on Mount Sinai. In it we are given God’s requirements for us in living this Christian life. We are called to be Holy as God is Holy. We are called to be Right in our actions as God is, which is Righteousness. Only those who are in Christ, with Christ in them, are able to do this although in a much diminished form from that of God Himself. The Righteousness Jesus is speaking of in v20 of Matthew 5 is not referring to the declaration of Righteousness that takes place when we are Justified by Faith. No, our Lord here is referring to our actions. Look at Matthew 5:6 and Matthew 5:10.
6 “Blessed are those who hunger and thirst for righteousness, for they shall be satisfied. Matthew 5:6 (NASB)
10 “Blessed are those who have been persecuted for the sake of righteousness, for theirs is the kingdom of heaven. Matthew 5:10 (NASB)
The Greek word for “righteousness” in vv6,10,20 is the same word, δικαιοσύνη (dikaliosune), it means either justice or righteousness. It describes one who is just or righteous. This is a person who is conformed to the claims of a higher authority. It can mean a state of being or the description of the actions of one who is righteous. In our justification at salvation, God declares us righteous in His eyes based on the work of Christ, not our works. However, in the three references in Matthew 5, Jesus describes what those who are righteous actually do. In v6 we have our Lord telling us that those who hunger and thirst for righteousness shall be satisfied or filled. In v10 we have our Lord telling us that when our righteous behaviour causes us to be persecuted then the kingdom of heaven is ours.