Now the adversaries of Israel come and they have offered to help Israel rebuild the temple, and the leaders [of Israel] give them their due and see right through it: these are idolaters. In other words, this is a test, this is an invitation to compromise to idolatry for pragmatic reasons. There is a certain level in which this would make sense. They could share in the work; they could share the new building; they could worship together. The exiles could show them the proper way to worship God. On the other hand, the peoples of the land are going to be eager to show them how they do it. There is a built-in conflict here; there is a built-in temptation to compromise. It is not a temptation that they can afford to face, and so there is an absolute separation that is insisted upon by the civil and religious authorities and amongst the exiles of that time.
Why? In order to preserve the true worship of the true God. In order to not mingle with idolaters. In order not to fall back into the old pattern. Why was Israel hauled off to Syria in the first place? Why was Judah hauled off to Babylon? Because of their idolatry. That lesson was learned finally through the destruction of Israel and Jerusalem and the exile. They are not going to repeat it again. Separation is absolutely essential as it touches theology and worship.1
Terry L. Johnson
1 Now when the adversaries of Judah and Benjamin heard that the returned exiles were building a temple to the LORD, the God of Israel,