Patristic Wisdom: Looking to the Sixth Sunday of Easter

If you love Me, keep My commandments. And I will pray the Father, and He will give you another Helper, that He may abide with you forever—the Spirit of truth, whom the world cannot receive, because it neither sees Him nor knows Him; but you know Him, for He dwells with you and will be in you. I will not leave you orphans; I will come to you. A little while longer and the world will see Me no more, but you will see Me. Because I live, you will live also. At that day you will know that I am in My Father, and you in Me, and I in you. He who has My commandments and keeps them, it is he who loves Me. And he who loves Me will be loved by My Father, and I will love him and manifest Myself to him. (John 14:15–21)

“In the first place,” he says, “it is appropriate for you to ask because you love Me and demonstrate your love by observing My commandments. And, because you are so disposed, I will confer the grace of the Holy Spirit so that you may always have it with you to teach you the truth.” He says another Paraclete, that is, another instructor, referring to Him as the Paraclete, meaning the comforter who will teach in times of tribulation, because the Spirit, through His grace, will lighten the sufferings inflicted upon them by humanity as He consoles them, through His gifts, and enables them to endure their afflictions, which is what actually happened. Indeed the more His disciples feared death previously, the more they rejoiced in tribulations after the descent of the Spirit. He calls Him the Spirit of truth, because He teaches nothing but the truth, since He is never inclined toward truth’s opposite that might otherwise cause Him to teach anything different from the truth. He also refers to the Spirit as another because while He [Jesus] was among them, He certainly filled this same role for them as well. In addition, they received from the Holy Spirit the confirmation of all those things that He had taught them when He was present, as our Lord also indicated, “But you will receive power when the Holy Spirit has come upon you; and you will be My witness in Jerusalem, in all Judea and among the Samaritans, and all nations.”

Theodore of Mopsuestia, Commentary on John 6.14.17