Charles Ellicott Commentary Nehemiah 13:20

"So the merchants and sellers of all kind of wares lodged without Jerusalem once or twice." — Nehemiah 13:20 (ASV)

Once or twice. —For a time they lodged outside; the impropriety of this, and the evidence it gave that they were only waiting to evade the law, made Nehemiah testify verbally and threaten forceful action. This effectively removed the evil.