If you were sincere in your faith when you were baptized, fell away from the Lord but have now come back with a repentant heart, the Lord already knows your condition, and as far as salvation there is no need for you to be baptized again. But if you want to do it as an outward symbol of your renewed commitment to the Lord, then that would be a positive action to take. We know that our relationship with the Lord is not about outward pomp and circumstance. But since water baptism is a core part of the Lord’s teachings and if you want to be baptized again out of respect to give glory to the Lord, and to show that the old man has been buried and the new man, raised up — baptized into Christ, then that would be a good thing to do. But do it with a contrite heart to honor the Lord, not to impress others.
“Or do you not know that as many of us as were baptized into Christ Jesus were baptized into His death? Therefore we were buried with Him through baptism into death, that just as Christ was raised from the dead by the glory of the Father, even so we also should walk in newness of life.
For if we have been united together in the likeness of His death, certainly we also shall be in the likeness of His resurrection, knowing this, that our old man was crucified with Him, that the body of sin might be done away with, that we should no longer be slaves of sin” (Romans 6:3-6).