The comments of the Catholic theologian Hans Küng in his book Christianity: The Religious Situation of Our Time on this passage are spot on:
“There is probably no better story in the New Testament to show us the relationship of Father, Son and Spirit than that of the speech made by the protomartyr Stephen in his own defence, which has been handed down to us by Luke in his Acts of the Apostles. During this speech Stephen has a vision: 'But he, full of the Holy Spirit, gazed into heaven and saw the glory of God, and Jesus standing at the right hand of God; and he said, “Behold, I see the heavens opened and the Son of man standing on the right hand of God.” So here we have God, Jesus the Son of Man, and the Holy Spirit. But Stephen does not see, say, a God with three faces, far less three men in the same form, nor any triangular symbol of the kind that was to be used centuries later in Western Christian art. Rather:
- The Holy Spirit is at Stephen's side, is in Stephen himself. The Spirit, the invisible power and might issuing from God, fills him fully and thus opens his eyes: in the Spirit heaven opens to him.
- God himself (ho theos = the God) remains hidden, is not in human form; only his 'glory' (Hebrew kabod, Greek doxa) is visible: God's splendour and power, the brilliance of light which issues fully from him.
- Finally Jesus, visible as the Son of Man, stands (and we already know the significance of this formula) at ‘the right hand of God’: that means in throne communion with God, in the same power and slory, Palled as Son of God and taken up into God's eternal life. He is God’s representative for us and at the same time, as a human being, the human representative before God.”