But he [Stephen], being full of the Holy Ghost, looked up stedfastly into heaven, and saw the glory of God, and Jesus standing on the right hand of God. And said, Behold, I see the heavens opened, and the Son of man standing on the right hand of God. (Acts 7:55-56 [KJV])
It is common for Latter-day Saints to cite Acts 7:55-56 as evidence of (1) that the Father and Son are separate persons and (2) that the Father has a “bodily form.” Point number 1 is something Trinitarians and most others will not dispute, though how one defines a “person” will differ (see the debate between Latin/Creedal and Social Trinitarianism, for instance, on this point). Point no. 2, however, is something most within the broad Christian spectrum will disagree with Latter-day Saints. Some may claim that Stephen only saw the “glory” of God (v.55), but only if one isolates this verse from the proceeding verse that speaks of Jesus being at the “right hand” of God (the Father).
A typical response to LDS usage of this verse as evidence for our theology is that the term, “right hand” can be used in a metaphorical sense. Therefore, they argue, it is being used in a metaphorical sense in this passage. There are a couple of things wrong with this approach, most notably it is the fallacy of undistributed middle—
First premise: Some instances of “right hand” are metaphorical.
Second premise: “Right hand” is used in Acts 7:55-56
Conclusion: Therefore, the use of the term, “right hand” is metaphorical in Acts 7:55-56.
The predicates in both the major and minor premises does not exhaust all the occurrences of this term and would therefore not necessitate such an interpretation in Acts 7:55-56. A more non-dogmatic and accurate conclusion would be that Acts 7:55-56 could have a metaphorical meaning, but such should be said with much caution as the argument for such a meaning is not nearly as simplistic as critics would like it to be.
It is true that the term can be used in a sense of authority (e.g. Biden is Obama’s “right hand man”). However, to claim that this is how it is to be interpreted in Acts 7:55-56 is eisegesis. This passage is describing what Stephen saw in vision; it is not a metaphorical for the relationship Jesus has with Father vis-à-vis authority. Indeed, what is being described is the spatial-relationship between the Father and the Son. Those who critique the LDS understanding have to ignore the literary genre of this pericope. Furthermore, the author of Acts 7:55-56 is alluding to a Messianic text from the Old Testament, Psa 110:1 (109:1, LXX). The LXX of this verse reads:
τῷ Δαυιδ ψαλμός εἶπεν ὁ κύριος τῷ κυρίῳ μου κάθου ἐκ δεξιῶν μου ἕως ἂν θῶ τοὺς ἐχθρούς σου ὑποπόδιον τῶν ποδῶν σου
Psalm of David: The Lord said to my lord, sit at my right hand, until I make your enemies your footstool (my translation)
Here, the first Lord (in the Hebrew, Yahweh) says to a second lord (adoni in Hebrew, meaning “my lord”) to sit at his right hand. The only meaningful, and exegetically sound interpretation of this verse is that the second lord is sitting at the right-hand of God, and not that he is the “right-hand man” of God (though he does indeed serve as God’s vizier, to be sure).
In Trinitarian theology, there is an allowance (albeit, an ambiguous one) for a distinction between the persons of the Father, Son and Spirit (e.g. the Father is not the Son). However, there is no allowance for a distinction between “God” and any of the persons. However, the Christology of the New Testament tends to distinguish “God” (θεος) from the Son, not simply the “Father” from the Son, as it does here, differentiating between ο θεος (literally, the God) from Jesus. Indeed, the other instances of the New Testament’s use of Psa 110:1 differentiates, not just the persons of the Father and the Son, but θεος and the Son. For instance, consider 1 Cor 15:22-28 and Heb 10:12-13:
For as in Adam all die, even so in Christ shall all be made alive. But every man in his own order. Christ the firstfruits; afterward they that are Christ's at his coming. Then cometh the end when he shall have delivered up the kingdom to God, even the Father; when he shall have put down all rule and all authority and power. For he must reign, till he hath put all enemies under his feet. The last enemy that shall be destroyed is death. For he hath put all things under his feet. But when he saith all things are put under him, it is manifest that he is expected, which did put all things under him. And when all things shall be subdued unto him, then shall the Son also himself be subject unto him that put all things under him, that God (θεος) may be all in all. (1 Cor 15:22-28)
But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God (θεος); From henceforth expecting till his enemies would be made a footstool for his feet. (Heb 10:12-13)
In both these pericopes, Psa 110:1 is used, and clearly, a distinction is made between, not just the persons of the Father and the Son (which is accepted, equivocatingly, by Trinitarian theology), but God (θεος) and Jesus, a distinction not tolerated by Trinitarianism, and something one also finds in Acts 7:55-56.
LDS apologist, Jeff Lindsay, provides a good LDS interaction with this pericope and common objections to its use here.