From The Giving Gift
In the writings of Luke the distinction between Son and Spirit is emphasized more strongly than anywhere else in the New Testament. In Luke’s account of the conception of Jesus, it is the Son who is born, but it is by the action of the Spirit that he is formed in Mary’s womb. In the baptism of Jesus, the implicitly Trinitarian element is at its clearest. The Father gives the Spirit to the Son, a statement that makes no sense unless Father, Spirit, and Son are in some sense three distinct entities, even if it is still not clear in this context to what extent the Spirit is being thought of in a fully personal way. The Spirit here is the Gift, the Father is Giver, and the Son is the recipient of that Gift.
Apart from reading Jesus’s quotation of Isaiah 61:1, “The Spirit of the Lord is upon me,” in his sermon at Nazareth, (4:17ff), Luke shows little interest in the participation of the Spirit in what Jesus did in Galilee. He portrays the ministry as the work of the Son. At the Ascension, which is recorded in both Luke and Acts, that work comes to an end and the Son withdraws. His going is followed after a short interval by the coming of the Spirit. In the gospel Jesus is at the center of the action and the Spirit is in the mysterious background. In Acts it is Jesus who has withdrawn into mystery and the Spirit who has moved into the spotlight, for it is he who is leading and empowering the mission of the church and the work of Peter and Paul. For Luke, the coming of the Spirit is not the return of Jesus but rather consequent upon the departure of Jesus. Here Son and Spirit are two rather than one.
It is, of course, important even in this Lukan context not to exaggerate the very real distinction between Son and Spirit. They are never separate or independent. In Acts it is Jesus who pours out the Spirit, (2:33). If at his baptism the Spirit is the Gift given to Jesus, at Pentecost he is the Gift given by Jesus. The Spirit comes from the Father through Jesus and the whole purpose of his coming is to empower the disciples in their witness to Jesus, (Acts 1:8). In Acts 16:7 the Spirit is described as “the Spirit of Jesus,” although what that means is never explained. So, to sum up, the bond between Jesus and the Spirit is always maintained even when, as here, the distinction between them is most evident. Nevertheless, for Luke, it is one thing to be filled with the Spirit on the day of Pentecost but quite another to travel the Damascus road and meet the risen and ascended Lord.