We understand that you're struggling with a recurring sin in your life, and we want to help you find freedom in Christ. First, let's address the issue of sin and repentance. In 1 John 1:8-9 (WEB) it says, "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and righteous to forgive us the sins, and to cleanse us from all unrighteousness." It's great that you've taken the step to repent and ask for forgiveness, but remember that repentance also involves a change of mind and turning away from the sin.
Masturbation is indeed a sin, as it is a form of sexual immorality. In 1 Corinthians 6:18 (WEB) it says, "Flee sexual immorality! 'Every sin that a man does is outside the body,' but he who commits sexual immorality sins against his own body." It's important to resist the temptation and flee from it, as Joseph did when he was tempted by Potiphar's wife in Genesis 39:12 (WEB), "She caught him by his garment, saying, 'Lie with me!' He left his garment in her hand, and ran out of the house."
The fact that you're feeling anxiety and depression after committing this sin shows that your conscience is at work, and the Holy Spirit is convicting you. It's not normal or healthy, despite what the world may say. In Romans 12:2 (WEB) it says, "Don't be conformed to this world, but be transformed by the renewing of your mind, so that you may prove what is the good, well-pleasing, and perfect will of God."
You mentioned that you've been sober from drugs and alcohol for over 500 days and have been celibate for 4 years, which is commendable. However, this sin is still holding you back from experiencing the fullness of life in Christ. In Hebrews 12:1 (WEB) it says, "Therefore let us also, seeing we are surrounded by so great a cloud of witnesses, lay aside every weight and the sin which so easily entangles us, and let us run with patience the race that is set before us."
Let's pray together for your deliverance and forgiveness:
Dear Heavenly Father,
We come before you in the name of Jesus Christ, lifting up our brother/sister in their struggle with sin. Lord, they have confessed and repented, and we ask that you would forgive them and cleanse them from all unrighteousness. Give them the strength and grace to flee from this temptation and to walk in the newness of life.
We also pray for their emotional well-being, that you would ease their anxiety and depression, and fill them with your peace and joy. Help them to draw near to you, and to experience the fullness of life in Christ.
We ask this in Jesus' name.
Remember, it is only by the name of Jesus Christ that we have access to God. In Acts 4:12 (WEB) it says, "There is salvation in none other, for neither is there any other name under heaven, that is given among men, by which we must be saved!"
Keep fighting the good fight of faith, and remember that you're not alone in this struggle. We are here to support and pray for you. Stay strong in the Lord and resist the devil, and we believe you will see victory in this area of your life.