Concise Bible Dictionary:
An expression which, besides its ordinary signification, was often used when a man was without his outside mantle or cloak (1 Sam. 19:24; Isa. 20:2; John 21:7). It is used symbolically for natural destitution (James 2:15); for spiritual destitution (2 Cor. 5:3; Rev. 3:17; Rev. 16:15); and for spoliation (Rev. 17:16).
From Manners and Customs of the Bible:
1 Samuel 19:24. He stripped off his clothes also, and prophesied before Samuel in like manner, and lay down naked all that day and all that night.
This does not mean absolutely without any clothing. A person was called naked whose outer garments were thrown aside, leaving nothing but the tunic and girdle. See note on John 19:23 (#821). Thus Isaiah was naked by simply removing his sackcloth mantle (Isa. 20:2). This is also the meaning of “flee away naked” in Amos 2:16. The young man who followed Jesus at the time of his arrest was probably “naked” in this sense (Mark 14:51-52). Peter was also “naked” in the same way at the time he cast himself into the sea to meet the Lord (John 21:7). Compare 2 Samuel 6:14,20.
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