It's a personal friendship
In these verses, God is referring to knowing someone as a personal friend. We get to know Him as a friend when we talk with Him daily, read His words, follow Him gladly, and freely share with Him our joys and sorrows as with an earthly friend. Jesus also says, “You are my friends if you do whatever I command you” (John 15:14). If we truly love Jesus, we will keep His commandments.
The people being addressed in Matthew 7:22 have rejected His Holy Spirit. They have embraced a theology of salvation in sin or salvation by works—neither of which needs Jesus. They are self-made people who did not take time to become acquainted with Jesus, even though they appeared to be doing His work.
Jesus doesn’t argue the fact that they performed many works in His name, maybe even miracles. It is possible to do good works and still lose out on salvation in the end. In this Scripture, He explains that He did not really get acquainted with them or know them as personal friends. These people were never converted and never placed their trust in His grace to save them.
Also, if we don’t know Jesus as a personal friend, if we are not working out of love for Him, our motives will be skewed. We could be doing works out of pride or envy, or possibly working from a belief or hope that we can earn our own salvation. Either pathway is wrong.
God wants us to have a special relationship of friendship, trust, and love. Then good works will flow naturally out of our intense love for our Redeemer and our desire to please Him.
KEY BIBLE TEXTS
Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? And then will I profess unto them, I never knew you: depart from me, ye that work iniquity. Matthew 7:22-23