Answer: As we had the Father and the Son in the first half of the chapter, the Spirit, another Paraclete or Advocate, introduces the second half at this point, Who when given should remain with the disciples forever (unlike Christ Who was leaving them for heaven), or, as it is added later, He remaineth with you and shall be in you. It is a mistake as old as Euthymius Zigabenus to fancy here a distinction between the then time and after Pentecost. The true sense is that, when given as at Pentecost, His was a permanent stay with them; and not only so, but He would be in them in a way peculiar to Himself, and only known since redemption. No doubt, He had acted on souls and in saints at all times, as we see in the O. T. throughout. But now His presence personally and forever was the fruit of Christ’s redemption and heavenly glory. The Father was revealed in the Son; the Son incarnate had done the will of God, consummating all sacrifice, and was received up as risen Man in glory; and the Holy Spirit, given and come forever, was the witness and power of all, both in the Christian and in the church; as we wait for the coming of the Lord to receive us to Himself and set us before the Father in His house, where Christ is now.