Samson went to Gaza, and saw there a prostitute, and went in to her.
We agree with Hervey that this episode "came many years after Samson's victory at Lehi, near the latter part of Samson's twenty-year judgeship."[7]  This appears to be evident from the mention of that 20-year interval in the last verse of  Judges 15, that being the purpose of its mention there, and not the indication of "separate sources," as some vainly suppose.  As Keil said regarding  Judges 15:20, "It is impossible to draw any critical conclusions from the position in which this remark occurs, as to a plurality of sources for the story of Samson."[8]