I'm not enough of a Scripture scholar to have much confidence in interpreting Paul's thinking on the Law, but I will suggest a way of looking at it that resonates with me. The trouble with Law, as I experience it, is that it becomes an unhealthy form of perfectionism. It sets up an unattainable standard, and then says that if you fail to measure up you are bad, wicked, a sinner, and condemned to eternal punishment.... We do have a remedy, in the form of the sacrament of reconciliation, a.k.a. confession to and absolution by a priest. But what is lacking there, for me, is any real support for my desire to do better next time. The standard is impossibly high -- not only "thou shalt not commit adultery", but "everyone who looks at a woman with lust has already committed adultery with her in his heart." In legalism, I feel like the grace of God comes in mostly after the fall, in the sacrament of confession. And I really appreciate having access to that sacrament, because the fall is going to come, and (along with making direct amends, when possible, when I've hurt someone else), it feels kind of like a "reset" button that makes it easier to pick myself up and start over. But avoiding the fall is all on us, and we are all guilty because will power is weak, we all fail, we all need the grace of forgiveness all the time.
Moreover, somehow it seems to me that external checklists of sins tend to encourage judging others by those standards as well, and then comparing their visible conduct against our own internal impulses. I know that I have looked at someone with lust, I am guilty. But I don't know if my buttoned-up, publicly virtuous co-worker stays up late watching porn, or molests his stepdaughter at home. I know that I'm guilty of snapping at people for interrupting when I'm trying to concentrate, but I don't know if the sweet, friendly lady down the street slaps her kids around when she's had too much to drink. Or the other way around: I judge another person harshly for their public sin, without having any idea what the private provocation or circumstances might have been.
Asceticism, on the other hand, says "yes, yes, we're all sinners, that's a given -- now what can we do about it?" Asceticism accepts right up front that perfection is unattainable. In fact, if you ever start to get puffed up with how much progress you're making in virtue, asceticism is bound to shoot you down with warnings about the deadly dangers of pride, vanity, and complacency. But this emphasis on humility, to me, seems very qualitatively different from the shame and guilt that I feel is bred by moral legalism. Humility is productive, shame is destructive.
Asceticism is fundamentally practical. It looks really hard at why we do the stupid, self-defeating, destructive things we do, and how we can gradually grow, and help others to grow, into healthier and holier ways of life. The monastic tradition picks apart the psyche, and although it gives the name "demons" to some of what it finds there, it still goes on to give us really useful tools for disarming the demons and arming our better angels.
The three primary tools of asceticism are prayer, fasting, and almsgiving. Prayer permeates the monastic life, from the formal communal liturgical prayers, to reflective reading of sacred texts, to private wordless contemplation. Prayer in all its forms acknowledges the insufficiency of our willpower and our dependence on God's grace, asks for help, lays us open to receive it, gives credit and thanks for it. Fasting stands for all the basic, ongoing work of self-discipline and taming what I called in my Rule of Life "the tyranny of capricious impulse." Almsgiving encompasses all the ways we get outside of ourselves and focus with compassion and empathy on other people, from overt acts of service, to patience with each other's weaknesses, to prayer on behalf of those whose suffering is outside of our reach.
To me, moral legalism is demoralizing: I will always fall short of its ideal, so it's always a fail. Monastic asceticism is encouraging: the ideal is the same, but it's about progress rather than perfection, and even sliding a step back doesn't discourage me from taking two forward. St. Benedict wrote in his Rule (chapter 64) that a good leader should push the monks hard, but with enough care and flexibility "that the strong may have something to strive after, and the weak may not fall back in dismay." In the prologue to the Rule, he calls the monastery a "school for the Lord's service," says he hopes nothing about it will be "harsh and burdensome," but also encourages us not to give up too easily when it does get hard, by saying that "as we advance in the religious life and in faith, our hearts expand and we run the way of God's commandments with unspeakable sweetness of love."
So what I think St. Paul is saying is that if you are ruled by a moral Law, then you are approved or condemned by God based on your compliance with that Law; but since no one can possibly live up to it all the time, in all its particulars, no matter how good your intentions, everyone is condemned. But what God did in the Incarnation, becoming human, joining Himself to ourselves, accepting human condemnation and execution, was to break that compact and set us free from condemnation under the moral Law. We sinners are approved, we are accepted and loved. Christ died not for the righteous (by the absolute standards of the Law, no one is righteous) but for sinners like us.
One last thought, to tie this all back in with what's going on in the world today. Today is the feast of St. Joseph the Worker, and I have been thinking of all those people whose work has been declared "non-essential." So many of us define ourselves and our worth by our work, and I wonder whether many of those left idle by this pandemic feel as if they themselves have been declared superfluous, as if the work they do has no essential value, as if they are no real use to anyone. But our worth is not defined by what we do. We are intrinsically good, loved, and counted worthy by God.
Catholic tradition distinguishes two kinds of religious life, the "active" and the "contemplative." The archetypal models for the two are the sisters Martha and Mary of Bethany, particularly in the story of Jesus's visit to their home in Luke 10:38-42. Martha bustles around serving Jesus and his disciples, but Mary just sits and listens to Him talk. Martha welcomes Him with her service, and Mary with her mere presence. Martha complains, but Jesus says that Mary has chosen the better part and it shall not be taken from her. Martha represents the religious orders who are out in the world serving the poor, feeding the hungry, teaching and nursing and all the rest of those essential works of mercy. Mary represents the cloistered monks and nuns (and hermits), who leave everything behind and whose primary work is simply to pray and to listen to God in their own hearts. We contemplatives are useless by the world's standards, but in Jesus's affirmation to Mary we know that we, too, are approved.
None of us has to earn God's love. Our worth is not dependent on any standard either of morality or of usefulness. God loves you! And I invite you to treat this time as an ascetic retreat. Think how you might apply the three pillars right now. Prayer: meditate, spend some time in nature, start a journal, draw. Fasting: think about what habits are dragging you down and make some changes, always keeping in mind "progress, not perfection." Almsgiving: look through your contacts list for people who might be having a hard time with the isolation right now and reach out with a phone call, ask an elderly neighbor if they need any help with outside chores or errands, or think of someone each day you can thank or compliment for something. And remember, sometimes the best "alms" you can give to someone else is the chance to help you! If you're struggling, give a friend or neighbor, or a hotline volunteer, the gift of your vulnerability, the gift of your trust, of your willingness to be in their debt.
Peace be with you!