First...keep the verse in context and you will see who this is addressed to.
21“Not everyone who says to Me, ‘Lord, Lord,’ will enter the kingdom of heaven, but he who does the will of My Father who is in heaven will enter. 22“Many will say to Me on that day, ‘Lord, Lord, did we not prophesy in Your name, and in Your name cast out demons, and in Your name perform many miracles?’ 23“And then I will declare to them, ‘I never knew you; DEPART FROM ME, YOU WHO PRACTICE LAWLESSNESS.’ (Matt 7:21-23)
Christ is talking to those who are not His followers. Do His followers practice lawlessness?
The Greek behind the word lawlessness means an utter disregard for God's law.
This does not describe Christians.
If your salvation is up to you then Christ died needlessly on the cross.
In addition, you've just shifted gaining Heaven from faith in Christ to what you do.....it's now about works. This goes completely against the Word and elevates a sinful man's efforts above a sinless Man's sacrifice.
Paul notes in Colossians 2:13-14 exactly what Christ has done for us.
When you were dead in your transgressions and the uncircumcision of your flesh, He made you alive together with Him, having forgiven us all our transgressions, 14having canceled out the certificate of debt consisting of decrees against us, which was hostile to us; and He has taken it out of the way, having nailed it to the cross.
Tell me again what you can do that surpasses this sacrifice by Christ?
And Abraham believed God and it was reckoned to him as righteousness.
Notice Abraham's faith came before circumcision, the Law, etc. There was nothing he did that earned his salvation.
And continuing today....there is no "work" or deed you can do that will earn your salvation.
We are saved through faith in Christ....not because of any good deed. The good deeds we do, "works", come about as a result of our faith in Christ.
As believers we are sealed by the Holy Spirit of promise who is given as a pledge of our inheritance (Eph 1:13-14). The Greek behind this indicates the Holy Spirit is given as earnest money....a pledge of a promise of a future payment.
It is my prayer that you come to faith in Christ so that you may know you have eternal life as He has promised.