Michael Bird, a New Testament scholar of the first rate, highlights Paul's statement in 1 Corinthians 8:3 that "anyone who loves God is known by him" before going on to quote Richard Hays' statement that "what counts is not so much our knowledge of God as God’s knowledge of us."
I don't know about how to rank these things, but I do know that my spiritual life underwent a remarkable change when I realized that God's knowledge of us was the foundation and precursor of our knowledge of Him, and that His knowledge, while intimate, is a source of comfort and joy. I also know that in treatments of Paul, his emphasis on God's knowledge of us gets too little attention. And no wonder. It seems to be an undercurrent in Paul's thought that only occasionally bubbles to the surface and becomes explicit. Consider the two other passages where Paul echoes his thoughts in 1 Corinthians 8:3.
First, 1 Corinthians 13:12: "For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall know fully, even as I am fully known." This comes, interestingly enough, at the end of Paul's magesterial explication of the love of God.
Second, Galatians 4:9: "For now that you have come to know God, or rather to be known by God, how can you turn back again to the weak and elementary principles of the world, whose slaves you want to be once more?" You can hear Paul catching himself--nope, it's not quite right that we know God, but rather, we are known by Him.
Paul is, I think, simply adopting some of the best of the Old Testament language of God's knowledge of us, not least of which is Psalm 139:
O Lord, you have searched me and known me!
2 You know when I sit down and when I rise up;
you discern my thoughts from afar.
3 You search out my path and my lying down
and are acquainted with all my ways.
4 Even before a word is on my tongue,
behold, O Lord, you know it altogether.
5 You hem me in, behind and before,
and lay your hand upon me.
6 Such knowledge is too wonderful for me;
it is high; I cannot attain it.
Our knowledge of God is enormously important. But for Paul, it is also eschatologically oriented. We know in part, but then we shall know fully. Meantime, we are to be grounded in and secured by God's knowledge of us and his accompanying love. For us, here and now, it is that which makes all the difference.