***(what is truly in their heart). We only know what we objectively observe.***
If they are sinning we have a pretty good idea what is going on in their heart.
If they are being nice and all it my be a Christian, or someone who has sin in their heart and trying get something.
You must have very limited experience in this thing we call life.
There are people we see steal, but suffer from a mental disorder. We see people do things we know as wrong, but were never taught.
We see any number of things which are objectively evil, like killing, but are mitigated by things such as self-preservation.
This list goes on and on.
We have no real idea what is going on inside the hearts and minds of our fellow man. For if we did, we would likely have more compassion.