And John bare record, saying, I saw the Spirit descending from heaven like a dove, and it abode upon him. John 1:32
But in the case of Jesus the coming of the Spirit was an equipment for life; it was the permanent indwelling of the Spirit in him. A surviving fragment of the Gospel according to the Hebrews, preserved by Jerome in his commentary on Isaiah 11:2, seems to seize upon this very point:
“And it came to pass, when the Lord was come up out of the water, the whole fount of the Holy Spirit descended and rested upon him, and said unto him; My Son, in all the prophets was I waiting for thee that thou shouldst come, and I might rest in thee. For thou art my rest, thou art my first-begotten Son, that reignest for ever.”
It was no portion of the Spirit which came upon Jesus; it was the very fountain of the Spirit. It was no temporary gift of the Spirit; it was the permanent abiding of the Spirit in him. In the moment of the baptism Jesus was divinely equipped for his task.
(Barclay, William., The Mind of Jesus, HarperSanFrancisco, United States of America, 1960, pg 29)