Living in fear that you may stumble again is not what we are told to do as Christians. We should all know that we may screw up again.
Living in fear causes anxiety and a feeling of thinking that you are in control of your own salvation based on what you do.
But we are not saved by what we do. We are saved because of what we believe. We believe that Jesus Christ is the Son of God and He is God and that he paid our sin debt.
Our job is simply to stand firm in the faith and act like men and women of God. We are His children. Adopted into his family because of the work of Christ and not because of anything that we do or that we might do.
Living in fear will cause you to not live up to the potential that God has created you with. God created you with a purpose and fear keeps you from that purpose.
“For you have not received a spirit of slavery leading to fear again, but you have received a spirit of adoption as sons by which we cry out, “Abba! Father!”
Romans 8:15 NASB
“Be on the alert, stand firm in the faith, act like men, be strong. Let all that you do be done in love.”
1 Corinthians 16:13-14 NASB
“Now there was a disciple at Damascus named Ananias; and the Lord said to him in a vision, “Ananias.” And he said, “Here I am, Lord.” And the Lord said to him, “Get up and go to the street called Straight, and inquire at the house of Judas for a man from Tarsus named Saul, for he is praying, and he has seen in a vision a man named Ananias come in and lay his hands on him, so that he might regain his sight.” But Ananias answered, “Lord, I have heard from many about this man, how much harm he did to Your saints at Jerusalem; and here he has authority from the chief priests to bind all who call on Your name.” But the Lord said to him, “Go, for he is a chosen instrument of Mine, to bear My name before the Gentiles and kings and the sons of Israel; for I will show him how much he must suffer for My name’s sake.”
Acts 9:10-16 NASB