1 Corinthians 4:5

So do not go on passing judgment before the appointed time, but wait until the Lord comes, for He will both bring to light things that are hidden in darkness and disclose the motives of the hearts. Then each one’s praises will come from God.

It is hard to understand the real motives behind an action without seeing what is happening in the heart. We don’t know by looking at a book’s cover what the words are written inside. We also don’t know what a person has experienced in this life to get them to this point. Until we understand that story, our judgment will be incomplete.