what's the difference? sin

So a sin is based on acting against divine law,

a transgression is an act or violation of a law or command IN GENERAL,

and iniquity is based on wickedness, so coming from a larger more serious moral scale.

I always wondered what the difference was between the words that the Bible used for sins. 

"He was crushed for our iniquities"

"He was pierced for our transgressions"

But they all come from a place of doing something against divine law = sin

So on the cross, Jesus bore the weight of ALL types of  sin, no matter how we define them as human beings. He took all of that on the cross with him.. no wonder God the Father had to look away.