John Wesley on Joshua 22:17

Of Peor - That is, of our worshipping of Baal - peor, Numb 25:3. Probably this is mentioned the rather, because Phinehas, the first commissioner in this treaty, had signalized himself in that matter: and because they were now at or near the very place, where that iniquity was committed. Are not cleansed - For though God had pardoned it, as to the national punishment of it, Numb 25:11, yet they were not yet throughly purged from it; partly because the shame and blot of that odious practice was not yet wiped off: and partly, because some of that corrupt leaven still remained among them, and though smothered for a time, yet was ready to break forth upon all occasions, See Jos 24:33. And God also took notice of these idolatrous inclinations in particular persons, and found out ways to punish them.