These things have I spoken unto you, while yet abiding with you.
Verse 25. Have I spoken. For your consolation and guidance. But, though he had said so many things to console them, yet the Spirit would be given also as their Comforter and Guide.
Christ stood by every word He taught you while present with you, He ratified it all, wasted no moment of His time with you. But He has arranged for another Teacher: the Father sends the Holy Spirit in His name, as His agent and representative, to carry on His work in your absence and ripen all things for His return.
AI summary
Commenting on John 14:25-27
Here we have a repeated promise of the mission of the Holy Ghost, called The Comforter, and his special office declared; namely, to teach, and to bring to remembrance what Christ had taught; He shall teach you all things. As the Spirit of God is the great Comforter, so he is the Special Teacher, of his children; he teacheth condescendingly, stooping to the meanest capacities...