Acts 1:15 - Joseph Benson’s Commentary on the Old and New Testaments

In those days While they were waiting for the promise of the Spirit; Peter stood up in the midst of the disciples Probably being under a peculiar divine influence on this occasion. The number of the names, or persons, together That is, who were together in the upper room; were a hundred and twenty It seems the greater part of the five hundred to whom Christ had appeared (see 1Co 15:6) continued in Galilee during this interval between the feast of the passover and that of pentecost. Dr. Lightfoot reckons that the eleven apostles, the seventy disciples, and about thirty-nine more, all of Christ's own kindred, country, and company, made up this one hundred and twenty; and that these were a sort of synod, or congregation of ministers, a standing presbytery, (Acts 4:23,) to whom none of the rest durst join themselves, Acts 5:13; and that they continued together till the persecution at Stephen's death dispersed them all but the apostles, Acts 8:1. But he thinks that, besides these, there were many hundreds, if not thousands, in Jerusalem at this time who believed; and indeed we read of many who believed on him there, but durst not confess him. Here was the beginning of the Christian Church; this one hundred and twenty was the grain of mustard-seed that was to grow into a tree, the leaven that was to leaven the whole lump.