“to godliness, brotherly kindness; and to brotherly kindness, love”
The first five virtues of verses 5-7 deal with our inner person—the last three deal with others. “Godliness” is the last of challenges to our inner life.
The word “godliness” appears in 2 Peter 1:3 (see our study there) and in 2 Peter 3:11. This is a word for piety but piety toward God; it carries the idea of reverence toward God.
An essential dimension of the Christian life is reverence for God.
The idea of piety in Scripture is not moroseness or a sullen solitary mode of life. It involves keeping close touch with God by faith, which produces a God-likeness.