John Calvin Commentary Exodus 23:28

"And I will send the hornet before thee, which shall drive out the Hivite, the Canaanite, and the Hittite, from before thee." — Exodus 23:28 (ASV)

And I will send hornets. Although that secret terror, which He had mentioned, would be sufficient to put their enemies to flight, He states that there would also be other ready means to rout them without any danger or much difficulty to His people. Yet He does not threaten to send great and powerful warriors, but only insects and hornets, as if to say that God would be so entirely favorable to His people that He would prepare and arm even the smallest animals to destroy their enemies.²⁷⁰

Thus the ease of their victory is shown, because, without the use of the sword, hornets alone would suffice to rout and exterminate their enemies.

He adds, however, an exception, so that the Israelites would not complain if the land was not immediately open to them, empty and cleared of its old inhabitants. He reminds them that it would be advantageous for them for Him to consume their enemies by degrees.

Although, therefore, God might at first glance seem to perform less than He had promised, and thus to retract or diminish His grace somewhat, yet Moses shows that in this respect He was also considering their welfare: to prevent wild beasts from rushing in upon the bare and desert land and proving more troublesome than the enemies themselves.

Indeed, it happened through the people’s negligence that they were long mixed with their enemies, because they executed God’s vengeance with too little energy. Indeed, His threat against them through Joshua was then fulfilled:

“if ye cleave unto the remnant of these nations, know for a certainty that the Lord your God will no more drive out any of these nations from before you; but they shall be snares and traps unto you, and scourges in your sides, and thorns in your eyes, until ye perish from off this good land, which the Lord your God hath given you.” (Joshua 23:12–13).

The fact, therefore, that these wicked and heathen nations were exterminated later, at the end of David’s reign, to deliver to the people the quiet possession of the land, must be attributed to their own fault, since unbelief and ingratitude rendered them inactive and disposed them to indulge their ease.

But, if no such inactivity had delayed the fulfillment of the promise, they would have found that the final destruction of the nations by God would have been delayed no longer than was good for them.

²⁷⁰ Few historical conjectures can be more striking than that of Dr. Hales, quoted in the Illustrated Commentary on Joshua 24:12, who supposes the “arma Jovis,” by which Virgil represents Saturn as having been driven to Italy, to have been the hornets here spoken of, and identifies the fugitive monarch with one of the Amorite kings, expelled before the armies of Joshua., who supposes the “arma Jovis,” by which Virgil represents Saturn as having been driven to Italy, to have been the hornets here spoken of, and identifies the fugitive monarch with one of the Amorite kings, expelled before the armies of Joshua.