19 And Yahweh was with Judah; and he drave out the inhabitants of the mountain; but could not drive out the inhabitants of the valley, because they had chariots of iron.

...how was it that Judah, having Yahweh with them, was unable to cope with the Canaanitish charioteers?

The answer is to be drawn from the fact illustrated at every stage of Israel's history, that though God was in their midst, His co operation was dependent upon their compliance with His pleasure.

When they lacked faith, doubted His word, or neglected His commandments, evil befel them, although He was in their midst. Thus, the first invasion of the Land of Promise was a failure, though Yahweh was in the camp (Num. 14: 40–45), because the congregation had not believed His word in the first instance, but had refused to go up to possess the land on account of the discouraging report of the spies, and now went up in opposition to instructions.

Again, Israel's attack upon Ai was repulsed, though God was with Israel, because there had been secret trespass in the congregation. The cause of Judah's powerlessness against the chariots of iron probably lay in his fright thereat; faith in Yahweh quailing in the presence of the ironclads. But, independently of this, of which there may be some doubt, a distinct cause of weakness appears in the incompleteness with which Judah and the other tribes carried out the divine instructions as to how they were to treat the subject nations. We learn from the very same chapter (verse 21) that

"the children of Benjamin did not drive out the Jebusites that inhabited Jerusalem."

"Neither (verse 27) did Manasseh drive out the inhabitants of Bethshean and her towns, nor Zanach and her towns, nor the inhabitants of Dor and her towns. . . It came to pass that when Israel was strong that they put the Canaanites to tribute, and did not drive them out."

So also we read of Ephraim (verse 29), Zebulon (30), Asher (31), Naphtali (33), &c. God's displeasure at this is thus declared in the next chapter: I have made you to go up out of Egypt, and have brought you into the land which I sware unto your fathers, and said,

"I will never break my covenant with you. And ye shall make no league with the inhabitants of this land: ye shall throw down their altars, but ye have not obeyed my voice: why have ye done this? Wherefore I also said, I will not drive them out from before you: but they shall be as thorns in your sides, and their gods shall be a snare unto you" (Jud 2:1–3).

Herein we perceive the cause of Judah's powerlessness, though Yahweh was with them. They were not working out the subjugation of the land in accordance with the commandments, and therefore Judah, though wishful, "could not drive out the inhabitants of the valley," who defended themselves in chariots of iron. These inhabitants were left as a thorn.

The Christadelphian, Jan 1898