score:4
But the way [Acts 15:28 is] phrased, and the context of the meeting, seem to point to the church having authority in this moment; that there's something special about these people being gathered together, under the guidance of the Holy Spirit, which gives them the right to make the decision and send the letter.
Yes. The early church leaders had the authority to decide what was and what wasn't Christianity. Paul's letters were not merely good advice. They were guidance for the various congregations.
Today, whether a church is part of a large denomination or an independent entity, somebody or some group runs the church. Administratively and doctrinally.
Hopefully, this leadership group runs the church with the counsel and guidance of the Holy Spirit. And the Holy Spirit is willing to guide the leadership group in harmony with God's will.
When the Spirit of truth comes, he will guide you into all the truth; for he will not speak on his own, but will speak whatever he hears, and he will declare to you the things that are to come. He will glorify me, because he will take what is mine and declare it to you. All that the Father has is mine. For this reason I said that he will take what is mine and declare it to you.
Upvote:2
Your hunch is correct; Reformed thinkers tend to reject the idea that there was some special authority inherent in this group. Instead, the authority comes from God, and the group is a faithful witness to it. Regarding this particular phrase, the 16th century Protestant/Reformed Geneva Study Bible says:
Not that men have any authority of themselves, but to show the faithfulness that they used in their ministry and labour. (source)
Similarly, John Calvin:
Whereas the apostles and elders match and join themselves with the Holy Ghost, they attribute nothing to themselves apart therein; but this speech importeth as much as if they should say, that the Holy Ghost was the captain, guide, and governor, and that they did set down, and decreed that which they write as he did indite it to them. (source)
So what, then, is the significance of "to us" here? Calvin sees Exodus 14:31 as a parallel:
Israel saw the great power that the Lord used against the Egyptians, so the people feared the Lord, and they believed in the Lord and in his servant Moses. [ESV]
Here, Calvin contends, the people of Israel did not attach themselves "partly to God, and partly to mortal man," but rather that they simply "gave credence to his minister." John Gill argues similarly, comparing the language of 1 Chronicles 13:2:
And David said to all the assembly of Israel, βIf it seems good to you and from the Lord our God, let us send abroad to our brothers who remain in all the lands of Israel..." (source)
In summary: Reformed theologians will tend to not view this phrase as indicating some special authority granted to this particular council. Instead, the authority comes from the Holy Spirit, and is bestowed on the council according to the faithfulness and diligence of its members.