The first prayer I learned as a child was the simple table grace: "God is great; God is good. And we thank Him for this food." I suppose this prayer is supposed to rhyme. It did when my grandmother said it because she pronounced food as if it rhymed with good or hood.
The two virtues assigned to God in this prayer, greatness and goodness, may be captured by one biblical word, holy. When we speak of God's holiness, we are accustomed to associating it almost exclusively with the purity and righteousness of God. Surely the idea of holiness contains these virtues, but they are not the primary meaning of holiness.
The biblical word holy has two distinct meanings. The primary meaning is "apartness" or "otherness." When we say that God is holy, we call attention to the profound difference between Him and all creatures. It refers to God's transcendent majesty, His august superiority, by virtue of which He is worthy of our honor, reverence, adoration, and worship. He is "other" or different from us in His glory. When the Bible speaks of holy objects or holy people or holy time, it refers to things that have been set apart, consecrated, or made different by the touch of God upon them. The ground where Moses stood near the burning bush was holy ground because God was present there in a special way. It was the nearness of the divine that made the ordinary suddenly extraordinary and the common, uncommon.
The secondary meaning of holy refers to God's pure and righteous actions. God does what is right. He never does what is wrong. God always acts in a righteous manner because His nature is holy. Thus, we can distinguish between the internal righteousness of God (His holy nature) and the external righteousness of God (His actions).
Because God is holy, He is both great and good. There is no evil mixed in with His goodness. When we are called to be holy, it does not mean that we share in God's divine majesty, but that we are to be different from our normal fallen sinfulness. We are called to mirror and reflect the moral character and activity of God. We are to imitate His goodness.