-ity: morality (the quality of being moral)
-ly: morally (in a moral way)
-ist: moralist (a person who is concerned with moral principles)
-istic: moralistic (excessively concerned with morality)
-ization: moralization (the act of making something moral)
-ize: moralize (to talk about morality in a way that is often preachy or judgmental)
The best suffix to use depends on the specific meaning you want to convey.