13:12 The night is far gone. Paul speaks here of the “night” of this present age. The “light of the world” has come (John 8:12), and we must prepare for the Second Advent of Christ and the age to come.

let us cast off . . . put on. The use of the metaphor “armor of light” stresses that developing positive spiritual graces, not merely rejecting vices, is essential to spiritual defense.