Herbert Spencer, one of the popularizes of agnosticism over a century ago, observed accurately that a bird has never been known to fly out of space. Therefore, he concluded by analogy that it is impossible for the finite to penetrate the infinite. Even if God does exist, we can never know Him personally or anything about His existence.
Spencer was right when he observed birds never fly out into space. His observation was correct, but his conclusion missed an important alternative possibility: God, the infinite Creator, could penetrate our finiteness - the Infinite could penetrate the finite, thereby communicating to us what He is really like. He could come to us......when we could not get to Him.
That is why Jesus came.
"The Word became flesh and made his dwelling among us. We have seen his glory, the glory of the one and only Son, who came from the Father, full of grace and truth." (John 1:14 NIV).
- Paul Little, Know Why You Believe, p. 43