Judges 18:15

‘ And they turned aside to it, and came to the house of the young man the Levite, even to the house of Micah, and asked him of his welfare.'

So they made a diversion and came to Micah's house and pretended that they had come to see the young Levite. Micah would happily receive them They had eaten at his table, thus he knew them to be friends. Once they were with the Levite, they asked him how he was faring. His reply would determine their next move.