God wants us to live in him. It's as simple as that. The main thing God wants both for us and from us is intimate union with himself. It's all over the pages of scripture; look no further than the upper room discourse (chapters 14-17 of John) to see exactly what I'm talking about:
Don't you believe that I am in the Father, and the Father is in me? The words I say to you are not just my own. Rather, it is the Father, living in me, who is doing his work. Believe me when I say that I am in the Father and the Father is in me..." (John 14:10-11)
Remain in me, and I will remain in you. No branch can bear fruit by itself; it must remain in the vine. Neither can you bear fruit unless you remain in me. (John 15:4)
Now remain in my love. (John 15:9)
...that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me. I have given them the glory that you gave me, that they may be one as we are one; I in them and you in me. May they be brought to complete unity to let the world know that you sent me and have loved them even as you have loved me. (John 17:21-23)
As Thomas Merton so beautifully pointed out in Thoughts in Solitude, God's desire is not that we live merely for him, or even with him, but to live in him. That is the kind of relationship he most desires with each of us. Anything short of that is settling for less than what God created us for. So let us not stop short of God's deepest desire. Let us always press on to live our lives in him. Let us live in loving, intimate union with he who made us for himself. Let us live in the abundance of his great affection. After all, that's what union with him is really all about.