When Christ says “Go and sin no more,” He is not saying “Quid pro quo.” He’s offering her a further gift: the gift of chastity. God’s generosity is pretty boundless, and He doesn’t expect repayment. He’s a Father. When you have kids and you impose rules on them, it’s not because you think that by following the rules the children will somehow make themselves worthy of your love and of the life that you have bestowed on them. Any parent can see that that’s just a crazy way of thinking about it – even though most of us have kids who think of it that way from time to time. The rules exist in order to keep the children happy and safe, not in order to make the kids pleasing to the parents. The kids are pleasing by default, even when they’re cranky, or get toothache, or snivel, or throw things at their siblings. There’s nothing that they can do in order to earn our love, or in order to make that love go away. In so far as we’re good parents, the things that we “demand” of our kids are actually gifts that we try to give them which happen to be arduous to receive. The gift of peace between siblings, the gift of self-control, the gift of a healthy body, the gift of a well-formed intellect, these are all gifts which we can bestow only if the child is willing to co-operate and is willing to work, trusting in the benevolent will of their mother or father. None the less, they are gifts which are intended for the good of the child.
It’s the same with God. Avoiding sin is not a bargaining chip that we offer to Jesus in order to make us worthy of His Body and Blood poured out on the cross. We are not called to avoid sin to pay our way out of Hell (which we can’t do anyways) or to prove to God that we really love Him. We are called to avoid sin because in doing so we are empowered to trust in God enough to recieve the gifts that He desperately wants to give to us.
This is why it is disastrous when the gift of chastity is presented to people as a demand, an exchange of happiness in this life for happiness in the next life. It’s not that at all. Chastity is good, not merely as a means of becoming a Saint in some future existence, but as a means of preserving dignity, integrity and happiness right now, in the present. The problem with Catholic outreach to sexual sinners is not that we don’t tell them the truth about the sinfulness of sin, but rather that we do not show them, by our actions and our words, that God’s love is bountiful, without limit, unmerited and unmeritable, available to all, capable of healing the most profound kinds of pain, utterly trustworthy, and directed towards the authentic goods of human life.”