A.T. Robertson Commentary 1 Thessalonians 5:4

"But ye, brethren, are not in darkness, that that day should overtake you as a thief:" — 1 Thessalonians 5:4 (ASV)

As a thief (ως κλεπτης). As in verse 2, but A B Bohairic have κλεπτας (thieves), turning the metaphor round.