Charles Ellicott Commentary Isaiah 57:14

"And he will say, Cast ye up, cast ye up, prepare the way, take up the stumbling-block out of the way of my people." — Isaiah 57:14 (ASV)

And shall say ... —Better, And one said. The prophet hears, so to speak, a voice behind him, bringing an oracle from Heaven, which renews the cry of the herald in Isaiah 40:3. The verb, cast up, points to the construction of the “highway” of a spiritual return, from which all impediments are removed.