Isaiah 40:10 - Matthew Poole's English Annotations on the Holy Bible

With strong hand; with invincible strength, conquering all his enemies. The word hand or arm may very well be understood out of the following clause. His arm shall rule for him; he shall need no succours, for his own power shall be sufficient to govern his people, and to destroy his adversaries. His reward is with him; he comes furnished with recompences, as well of mercy and blessings for his friends and followers, as of justice and vengeance for his enemies. His work before him; he carrieth on his work or design effectually, so as none can hinder him; for that is said in Scripture to be before a man which is in his power, as Genesis 20:15, Genesis 24:51, &c. Or work is here put for the reward of the work, as it is Isaiah 49:4, Isaiah 65:7, and elsewhere. And so the same thing is repeated in other words, as is very usual.