Waiting In The Upper Room
Following the Ascension, the eleven apostles, along with Mary the mother of Jesus and His brothers, have returned to Jerusalem. They have taken up residence in an upper room, devoting themselves to continuous, unified prayer. The group numbers about one hundred and twenty persons. They are actively waiting for the promised Holy Spirit.
The atmosphere is one of disciplined expectation. There is no frantic organizing or debate; there is simply prayer. They are honoring the final command of the Master to stay in the city until they are clothed with power from on high. This upper room has become the spiritual incubator for the birth of the Church.
— Acts 1:14