If God be glorified in him - If God is honored by him. If the life and death of the Messiah be such as to lead to the honor of God, such as shall manifest its perfections, and show his goodness, truth, and justice, then he will show that he thus approves his work.
God shall also glorify him - He will honor the Messiah. He will not suffer him to go without a proper attestation of his acceptance, and of the honor that God puts on him. Jesus here confidently anticipated that the Father would show that he was pleased with what he had done. He did it in the miracles that attended his death, in his resurrection, ascension, exaltation, and in the success of the gospel. We may remark that God will always, in the proper time and way, manifest his approbation of those who live so as to promote the honor of his name.
In himself - Or by himself; by a direct and public expression of his approbation. Not by the ministry of angels or by any other subordinate attestation, but by an expression that shall be direct from him. This was done by his direct interposition in his resurrection and ascension to heaven.
Shall straightway - Immediately, or without delay. This refers to the fact that the time when God would put this honor on him was at hand. His death, resurrection, and ascension were near.