What did the thief on the cross give up?It means sinners must be willing to give up everything to get saved or they will not be granted forgiveness.
I don't believe acts of penance or procedures of repentance as human works of contrition will be judged by God as worthy of forgiveness and salvation. But nobody who refuses to give up sin, who refuses to turn away from sin, who does not demonstrate before God a desire to exchange sin for God's righteousness, and to be delivered from the pleasures of sin in his life can get saved.
Proverbs 28:13. He that covereth his sins shall not prosper: but who confesseth and forsaketh them shall have mercy.
Repentance is not about turning from sin to be saved. Repentance is turning to Jesus who died for our sins. Repenting from sins, for salvation, is a false gospel. It's blasphemous.