You and I live in a post-modern world that questions our absolute trust in God, and one of the things you’ll often hear is that you can’t be certain of God unless you know Him perfectly.
A post-modernist is likely to ask you: “Do you know everything there is to know about God?”
My honest answer would be: “No, I’m afraid I don’t know everything there is to know about God. There are limits to my human intelligence, and so, no, I don’t know Him perfectly.”
Then he’ll say, “Well, how can you possibly say you know God?”
Christians often get overwhelmed with this line of argument. My response to it is this: “I’ve never claimed to know God perfectly or completely. But the beautiful thing is, He knows you and me perfectly!”
1 Corinthians 13:12 says, Now we see only a reflection as in a mirror; then we shall see face to face. Now I know in part, then I shall know [Him] fully, even as I am fully known.
It’s true that God’s ways are higher than ours, but even now the Spirit of God can impress things upon your heart with a deep sense of conviction. And God says this is knowing. God says there are certain things through the Holy Spirit that you and I can know. The only way that we know anything about God is through what God says and the truth He’s chosen to reveal to us. We can know nothing about God based simply on human speculation.