A.T. Robertson Commentary Acts 15:30

"So they, when they were dismissed, came down to Antioch; and having gathered the multitude together, they delivered the epistle." — Acts 15:30 (ASV)

So they (ο μεν ουν). As in verse 3.

When they were dismissed (απολυθεντες). First aorist passive participle of απολυω, common verb to loosen, to dismiss. Possibly (Hackett) religious services were held as in verse 33 (cf. 13:3) and perhaps an escort for part of the way as in verse 3.

The multitude (το πληθος). Public meeting of the church as in verses 1-3. Deissmann (Bible Studies, p. 232) gives illustrations from the inscriptions of the use of πληθος for official, political, and religious gatherings. The committee formally "delivered" (επεδωκαν) the epistle to the church authorities.