‘ And there was a young man out of Bethlehem-judah, of the family of Judah, who was a Levite, and he sojourned there.'
There were two Bethlehems, one in the tribe of Zebulun, (Joshua 19:15), and this in the tribe of Judah. This Bethlehem occurs twice in the narrative, as a source here of a dishonest Levite and in Judges 19:1 of a faithless concubine (see also Ruth 1:1). They were not good advertisements for the moral state of Bethlehem-judah.
From there came a young man who was a Levite with connections with Judah. The Levites were scattered throughout the whole of Israel and ‘adopted' into their various tribes, but only as sojourners. Thus this man had become a member of the family of Judah while retaining his Levite identity. The fact that he ‘sojourned', took up residence among them there (compare Judges 19:1 of another Levite), when it was not a Levitical city, was a further sign of the state of affairs in the country, although the Levites may have had a ministry of guiding the people (‘to bless in His name' - Deuteronomy 10:8). ‘Sojourner' strictly referred to a resident alien. But Levites were seen as sojourners because they belonged to God, not as being one of the people.
God's theoretical blueprint as described in the Law of Moses would have produced a strong and fair nation, avoiding the excesses of kingship, satisfying its religious needs, always united and powerful, looking to Yahweh for guidance and deliverance, the perfect theocracy. But unfortunately human beings were involved. Thus the blueprint was in process of time adapted and altered to suit man's convenience, desires and local customs, until it was only partially recognisable and very much distorted, with the result that it failed in its purpose due to the weakness of its participants.
And this affected no one more than the Levites, men set aside for the service of the Tabernacle and to make the Law known, who retained respect and deference in the community as men of God, but who came far short of the ideal. Indeed, as with this man, many took advantage of their status to advance their own wealth and position and were not too particular about the legal requirements of the Law.