After we accept Christ as our saviour we can renounce our past involvement with any works of darkness. We can take it further even renouncing works of darkness of our ancestors.
Renunciation prayers are a form of repentance which can give deliverance. Repenting of our sins can help to cleanse us from unrighteousness and renunciation of the sins of our ancestors can help to release us from the effects of their sins and inquity.
Specific prayers to renounce freemasonry, witchcraft and the occult, etc. can be found on this site and elsewhere on the internet. Some are long but worth saying as they only need to be said once.
This prayer though could be said from time to time as part of our spiritual warfare, to help close demonic doorways or open portals, and tear down demonic strongholds, giving demons licence grounds or legal rights to harass and torment in all the ways that they do, whether through health, financial or relationship problems, etc. Remember that demons get a toehold, a foothold, a stronghold and then a stranglehold.
Renunciation prayers are best said aloud, and for women with their head covered. If you would like to, it could be helpful to go through written prayers beforehand and make your own version, including specific names, etc.
I forgive any person who has ever hurt me, disappointed me, abandoned me, mistreated me, or rejected me in the name of Jesus.
I renounce all hatred, anger, aggression, resentment, revenge, retaliation, unforgiveness and bitterness in the name of Jesus.
I renounce all pride, haughtiness, arrogance, vanity, ego, disobedience and rebellion in the name of Jesus.
I renounce all envy, jealousy, and covetousness in the name of Jesus.
I renounce all selfishness, self-will, self-pity, self-rejection, self-hatred and self-promotion in the name of Jesus.
I renounce all backsliding, ingratitude, unthankfulness, murmuring, complaining and falsely accusing.
I renounce all lust, perversion, immorality, uncleanness, impurity, and sexual sin in the name of Jesus.
I renounce all addiction to drugs, alcohol, or any legal or illegal substance that has bound me in the name of Jesus.
I renounce all witchcraft, sorcery, divination, and occult involvement in the name of Jesus.
I renounce all ungodly soul ties and immoral relationships in the name of Jesus.
I renounce all ungodly covenants, oaths and vows made by myself or my ancestors in the name of Jesus.
I renounce all ungodly thought patterns and belief systems in the name of Jesus.
Thank you Father for deliverance and salvation we are given through the name of Jesus.
For further reading: The Occult and Cursed Object List