In chapters 23 through 25 what does Dantes mean by his "farewell" to kindness, humanity, and gratitude?

At the end of Chapter 19, Dantès has now used his wealth to perform all sorts of good deeds — to reinstate Monsieur Morrel and to re-establish the Morrel family name. The rest of the novel will show how Dantès (now about to assume the identity of the Count of Monte Cristo) effects his revenue upon his enemies. As Dantès himself expresses it: "And now farewell to kindness, humanity, and gratitude. Farewell to all sentiments that gladden the heart. I have substituted myself for Providence in rewarding the good. May the God of Vengeance now yield me His place to punish the wicked!"