It is incompatible with the concept of a just god.
But the core of the Christian message is that God care more about mercy than justice.
Horrible dichotomy, IHMO. The assumption (that in my understanding is not part of the Jewish understanding of human nature) is total depravity.
Jesus showed both mercy and justice to the woman caught in the act of adultery. While the text (John 7:53 - 8:11) leaves this out, I'm sure the woman was weeping, and sorry.
Even today we use the phrase "contrary to equity and good conscience" to describe an unjustifiable denial of service, benefits, etc. Justice and mercy are not incompatible.