It’s a happy fact that many discussions of Natural Law take marriage as their starting point, as this is certainly the origin of all contracts and communal life. As I’ll point out later on, this beginning of human relationships is also the paradigm for our destiny and end.
You are aware of the complex inter-weaving of the concepts of sin, death, and law that Paul presents in his Epistle to the Romans. Jewish notions of freedom are all rooted in the Exodus, a journey out of bondage. Christ’s passion and resurrection fullfills and reveals the Jewish deliverance. Thus, the Exodus is no longer politics, but prophecy: Egypt is the land of bondage, but also the land of Death, from which the Israelites are delivered by the paschal event. Christian notions of freedom are all rooted in the fact of the Resurrection. You can’t be any less free than you are when you’re dead. You can’t be any more free than to be God, who’s subject to no law, and is preeminently, demonstrably not-subject to death. Thus, the closer to authentic freedom we get, the closer we are to God. For the soul to be free, conscience and will must be free. In order to be free, they must have access to truth. Christ’s teaching that “the truth shall set you free” must be understood not as political, but salvific.
God comes to man not as rapist, but as Bridegroom. Having created us free in will, having purposed us to partake of his own divine life, he seeks not the “Islam” of submission to irresistable will, but the “Yes” of a beloved Spouse. Many Orthodox theologians, whose liturgy encourages them to keep their eyes fixed firmly on the Resurrection with a vividness and immediacy seldom appreciated in the West, have a clearer understanding of how the New Covenant shatters the legalistic relationship, replacing it with marital intimacy, heirship in the Kingdom, and theosis: a direct taking-up and participation in the Trinitarian communion. Christos Yannaras in The Freedom of Morality presents a memorable explanation of how conventional ethics and moral law, if observed as the end of life in themselves, are actually an impediment to the trinitarian life. It’s a species of coercion that Paul Evdokimov calls a “terrorist” theology, utterly at odds with Jesus, who lays down his life not out of compulsion but of his own free will, of God who seeks but does not compel the “fiat” of the Virgin Mary.
I am not deeply read in theology, so be warned: I may be wandering off the reservation and not even know it. I expect to have some follow up comments, but want to think them over first. Hope this helps.