Jamieson, Fausset and Brown on 2 Kings 7:3

3. there were four leprous men--The account of the sudden raising of the siege and the unexpected supply given to the famishing inhabitants of Samaria, is introduced by a narrative of the visit and discovery, by these poor creatures, of the extraordinary flight of the Syrians.

leprous men at the entering in of the gate--living, perhaps, in some lazar house there (Le 13:4-6; Nu 5:3).