Found only in Phil. 4:8; 1 Pet. 2:9; 2 Pet. 1:3, 5 the Greek noun “arete” meant “virtue,” “good conduct,” “praise,” or “moral excellence.”
In Phil. 4:8 and 2 Pet. 1:5 this noun describes the “excellence of life” Christians are to demonstrate. Definitions for this word in 1 Pet. 2:9 are difficult, but one of the better meanings seems to be “praiseworthy acts. These are to be proclaimed by the old people of God and by the new” (Dictionary of New Testament Theology, 3:927). A good definition for 2 Pet. 1:3 is “God’s attribute of perfection, which through its manifestations of power (dynameis) has granted gifts to men, by which they in their turn, as v. 4 puts it, are to become partakers of the divine nature” (ibid).