Isaiah represents the Gospel as being completely successful in accomplishing the purpose for which it was sent into the world:
That, as the rain and snow come down from heaven, and retmi not thither, but water the earth, and cause it to bring forth and bud, so shall the word of God be; it shall not return void, but it shall accomplish the divine pleasure, and prosper in the thing for which God sent it. (Isa. 45:10,11)
Thus all who allow that God sent the Gospel to benefit all mankind, must here see, that that beneficent object will surely be accomplished. If any reject the Gospel, and are lost forever, can it be said in truth, that God’s word does not return unto Him void?
From “100 Scriptural Proofs That Jesus Christ Will Save All Mankind” by Thomas Whittemore.