"That is why Christians are told not to judge.  We see only the results which a man's choices make out of his raw material.  But God does not judge him on the raw material at all, but on what he has done with it."  Mere Christianity

We do not see each other as we really are.  This, says Lewis, is the reason why we ought not to judge one another.  The cause of what we think is sin in another person may not be that person's choice at all.  And the cause of what we think virtue in ourselves may only be our good upbringing.

This leads to the fact that we will certainly have many surprises in heaven.  John Newton may have been the first to suggest that there will be three surprises in heaven.  The first surprise will be seeing many people there whom I did not expect to see there.  The second surprise in heaven will be missing many whom I did expect to see there.  And the third surprise will be that I  am there; that third surprise is the surprise of grace!

Lewis suggests in his sermon, The Weight of Glory, that rather than judging people for the way they appear to us now, we should focus on the fact that:

It is a serious thing to live in a society of possible gods and goddesses, to remember that the dullest and most uninteresting person you can talk to may one day be a creature which, if you saw it now, you would be strongly tempted to worship, or else a horror and a corruption such as you now meet, if at all, only in a nightmare.  All day long we are, in some degree, helping each other to one or other of these destinations.

What destination are we helping our neighbors toward this day, this very moment?

Dear friends, now we are children of God, and what we will be has not yet been made known.  But we know that when he appears, we shall be like him, for we shall see him as he is (1 John 3:2).

Father, thank you for adopting me as one of your children through Jesus Christ your Son, and shaping me every day to be more like Christ.  Help me, by your Holy Spirit, not to waste any more time in judging your other children.  Rather, help me to spend the rest of my days helping others to their final destination in you through loving them as I love myself, that is--doing what is best for their eternal glory and yours.  Amen.