Q. “I charge thee before God... and the elect angels” (1 Tim. 5:21)?
A. The elect angels are the witnesses of God’s preserving a creature unfallen; men, the saints, of His redemption of creatures who have fallen. The fallen angels are those who exercised their own will without a tempter, as man, and lost their place irrecoverably. They are reserved in chains under darkness until the judgment of the great day. Angels are either “elect” or “fallen,” as far as I know from Scripture.