In Chapter 4 of The Divine Names, Dionysius says:
Now if the Good is above all things (as indeed It is) Its Formless Nature produces all-form; and in It alone Not-Being is an excess of Being, and Lifelessness an excess of Life and Its Mindless state is an excess of Wisdom, and all the Attributes of the Good we express in a transcendent manner by negative images.
Now this is not especially easy to understand. But Dionysius seems to be saying that God does not posses life or mind in a literal sense, but is rather above these things, much as held by Plotinus. Possibly somewhat in contrast, he seems to believe that “Good” is an especially appropriate name for God.
According to the account we have given of being and the good, this is correct. If the good is that towards which things tend, then a necessary being must above all be good, because it has such a deep tendency to be that it cannot not be. Likewise, insofar as the good is understood as a final cause of other things, and thus as an ultimate explanation, while the first cause can have nothing else explaining its existence, it must constitute the supreme good not only in relation to itself, but in relation to all other things as well.