Zechariah 12:5

He still continues the same subject — that however small and feeble the flock of God would be, it would yet have sufficient strength; for the Lord would stand on the side of those who fled to him. Though then Jerusalem was not as yet filled with citizens, and though there was but one city, yet Zechariah testifies that its strength would be invincible; but he speaks of the chiefs of Judah comparatively. Formerly, we know, it had a great number of men, and great armies were raised from that one tribe and the half tribe of Benjamin. Though then there were formerly many provinces, though the country was full of populous towns, yet almost Jerusalem alone had then begun to be inhabited: but the Prophet says here, that though the whole Church was gathered within the narrow bounds of one city, it would yet have sufficient strength to resist all the attacks of enemies.

Say then shall the chiefs of Judah; that is, though formerly the governors or commanders of thousands had forces in their several towns, yet now all would look to one city; for the land was nearly forsaken and without inhabitants; at the same time they were to entertain hope, for their strength was to be in the Lord. Some insert a conjunction, “Strength will be to me and to the citizens of Jerusalem;” but they pervert the meaning; for the Prophet meant to say in one sentence what I have stated — that the eyes of all would be directed to one city only, and that yet there would be sufficient ground for hope and confidence, for they would become strong, not in themselves, but in their God.

There is a change of number, when he says, a strength to me, for he had spoken of chiefs; it ought then to have been לנו, lanu, to us. But he now introduces each of them as speaking, as though he had said, “No one of the chiefs shall look to his own land, but, on the contrary, direct his eyes to the holy city, and be content with the defense of a few men.” Hence he says, In Jehovah of hosts, their God; for he means that God would be then the protector of that people whom he had for a time forsaken. And he calls him again the Jehovah of hosts, in order to set forth his invincible power, lest the minds of the godly should fail through fear, on seeing themselves far unequal to their enemies. (156) It follows —

And say will the chiefs of Judah in their heart, —
“Strength beto the inhabitants of Jerusalem
Through Jehovah of hosts, their God.”

To stay in the heart is to pray, to utter a secret prayer; and the prayer is stated in the following lines. This was to show that there would be discord or emulation between Judah, the people of the country, and the city Jerusalem. And in the following verses we find both mentioned, as liable to envy, especially in verse 7. — Ed.