On another forum there was a discussion, and the name of Karl Barth turned up, one of the most well known Protestant theologians of the 20th century. His "Church Dogmatics" runs into several volumes ( this, not always a good sign....

). But it was said that Barth came within an inch of equating original sin with free will.
This was offered in part after some words of Thomas Merton were quoted, which in some ways says the very same thing....
The mere ability to choose between good and evil is the lowest limit of freedom, and the only thing that is free about it is the fact that we can still choose good.
To the extent that you are free to choose evil, you are not free. An evil choice destroys freedom.
We can never choose evil as evil: only as an apparent good. But when we decide to do something that seems to us to be good when it is not really so, we are doing something that we do not really want to do, and therefore we are not really free.
Perfect spiritual freedom is a total inability to make any evil choice. When everything you desire is truly good and every choice not only aspires to that good but attains it, then you are free because you do everything that you want, every act of your will ends in perfect fulfillment.
Freedom therefore does not consist in an equal balance between good and evil choices but in the perfect love and acceptance of what is really good and the perfect hatred and rejection of what is evil, so that everything you do is good and makes you happy, and you refuse and deny and ignore every possibility that might lead to unhappiness and self-deception and grief. Only the man who has rejected all evil so completely that he is unable to desire it at all, is truly free. God, in whom there is absolutely no shadow or possibility of evil or of sin, is infinitely free. In fact, he is Freedom.
(From "New Seeds of Contemplation")
So, to live is to "sin", to choose is to "sin" - until we are one with the Divine. And to become one with the divine is by Grace, which has been expressed in Christian mystical language.........."In giving us His love God has given us His holy spirit so that we can love Him with the love wherewith He loves himself. We love God with His own love; awareness of it deifies us." It is not of "ourselves".
Such expressions have the approval of certain Buddhists (which I feel bound to say, seeing no restrictions on "grace") The Buddhist way has many parallels with the apophatic Christian Tradition, the way of Unknowing, or the negative way. Most of which is above my head, apart from just being aware that what is of "myself", seems more often than not a constant stream of pettiness, judgements and a host of other things that should not be mentioned on a family forum! But for me, this is "seen" in the warm light of infinite compassion, and it is this light that transforms such baseness to a love that just sometimes I get glimpses of, or rather, am able to express.
In the meantime, as I wallow, there are the words of Julian of Norwich....
If there be anywhere on earth a lover of God who is always kept safe, I know nothing of it, for it was not shown to me. But this was shown: that in falling and rising again we are always kept in that same precious love.
And, just for the sake of Inter-faith dialogue, a verse from the hymns of Shinran, a 12th century Japanese man of the Buddhist Pure Land faith...
My eyes being hindered by blind passions,
I cannot perceive the light that grasps me;
Yet the great compassion, without tiring,
Illumines me always.
Which says much the same thing.