By “convicted” we mean convicted by the court. If a case remains unnoticed and the person involved knows that such and such person is committing this sin he should not propagate the sin. When the individual realizes his sin he needs to seek God's forgiveness and keep it to himself. Please note that these rules are social. Indulgence in zina is of course sinful. One has to be held answerable before at least the court of the Almighty. As long as the issue remains between the man and the Almighty we cannot say he is not allowed to marry a chaste woman or keep a chaste wife even after committing zina. If he is a God-fearing man and comes to realize his sin he will seek God's forgiveness and repent truly. It is upon God to forgive or punish him. No one is allowed to say anything to him. Nor even another person who knows the fact.