Charles Spurgeon Commentary Deuteronomy 32:27

"Were it not that I feared the provocation of the enemy, Lest their adversaries should judge amiss, Lest they should say, Our hand is exalted, And Jehovah hath not done all this." — Deuteronomy 32:27 (ASV)

That I feared the wrath of the enemy, lest their adversaries should behave themselves strangely, and lest they should say, Our hand is high, and the LORD hath not done all this.

So he spared them for his own name's sake; and, to this day, when God can find no other reason for showing mercy to the guilty, he does it for his name's sake.

And this is a blessed plea, to be urged by a man who can see no reason why God should have mercy upon him.

He may say, "Lord, do it for your name's sake, to make your grace and your mercy illustrious, in the salvation of such a poor, hopeless wretch as I am."