ephod. Probably the priests were lax in restoring the worship of the true God. So that Gideon would have meant well and desired to judge well. Compare Judges 17:5, where Micah made another. The reason given being that "there was no king, and every man did what was right in his own eyes", Judges 17:6. and Judges 18:5, where it was used to "ask counsel"; and for the same reason, Judges 18:1.
Related Commentaries of Judges 8:27
Judges 8:27
27 And Gideon made an ephod thereof, and put it in his city, even in Ophrah: and all Israel went thither a whoring after it: which thing became a snare unto Gideon, and to his house.