I love this nuanced understanding of karma in action:
"A person disposed to anger will more and more easily erupt in anger anew at any provocation. But in a moment of kindness a kindly disposition is deposited, and one becomes incrementally more disposed to kindness. The attitude with which we respond to an object of experience, with anger or with kindness, will therefore not only influence the causal field outside ourselves but also progressively reshape our very nature."
~ Andrew Olendzki, "Karma in Action"