We must not take our salvation in Christ for granted.
“I must write…urging you to stoutly defend the truth that God gave once for all to hHis people to keep without change through the years.”
Once we are saved, yes, we are never required to say the Prayer of Salvation (Romans 10:9), again. However, that doesn’t mean we have permission to compromise Christ’s righteousness through our sin.
“Some godless teachers have wormed their way in among you, saying that after we become Christians we can do just as we like without fear of God’s punishment.”
However, once we have believed, our life is meant to be an ever-growing, living testimony of that confession.
“But you, dear friends, must build up your lives ever more strongly upon the foundation of our holy faith, learning to pray in the power and strength of the Holy Spirit. Stay always within the boundaries where God’s love can reach and bless you.”
If your life today is not a living testimony of Christ, I hope you’ll stop and pray. Repent. Be restored to a place of right standing with Christ. It is possible, you know, to fall away from that great Salvation Christ won for you on the cross at Calvary. I don’t think you want that to happen.