Explaining Religion and God to Kids
You can be proud of your son and his questions! I would answer him in two parts. First, I would remind him that he can always talk to God—that's what prayer is. And if he listens carefully, God's answer will be heard in his head and his heart.
As for seeing God, that's a different matter. I would tell your son that God plays "hide & seek." If we seek evidence of God, we will find it in our relationships with the people we love, the ways we help others and in the beauty of the world around us. You can remind your son that you put love in every bedtime story you read and every meal you prepare. But although he feels it, he can't see it. Reassure your son that God is always with us, hoping we will seek and find!
Here are some good books for young kids on this issue: