blessed are those who do not see

Why was Thomas in a less favourable position to ourselves? Why is it a blessing to believe without seeing? Again, this is related to the opening questions in this blog...
I think it all has something to do with this: God wants us to know him as the one who gives sight to the blind, and life to the dead - and so he withdraws the risen Jesus from our sight, offering us only the testimony of the cross and resurrection, delivered by followers of the hidden Lord.

So is our positive reception of this message effectively a nullification of all of our previous contemplations and searchings and ponderings? Does grace, in this sense, destroy nature - or does it come as the corrective perfecting of our previous groping for God? Of course, there is a long and heated theological debate. Luther and Barth are often thought of as being the key representatives of the idea that grace destroys nature, in opposition to Aquinas, who represents the idea that grace perfects nature.

I wonder if it would be fruitful to think about it like this: Grace resurrects nature... that is, the grace of God is not continuous with any human foundations - it crucifies human pride... on the other hand, the grace of God does enliven and bring to fullness the genuine personhood that had been crudely existent before the coming of salvific grace. In this sense, grace genuinely destroys and perfects.