Acts 6-New International Version (NIV) The Choosing of the Seven
6 In those days when the number of disciples was increasing, the Hellenistic Jews[a] among them complained against the Hebraic Jews because their widows were being overlooked in the daily distribution of food. 2 So the Twelve gathered all the disciples together and said, “It would not be right for us to neglect the ministry of the word of God in order to wait on tables. 3 Brothers and sisters, choose seven men from among you who are known to be full of the Spirit and wisdom. We will turn this responsibility over to them 4 and will give our attention to prayer and the ministry of the word.” 5 This proposal pleased the whole group. They chose Stephen, a man full of faith and of the Holy Spirit; also Philip, Procorus, Nicanor, Timon, Parmenas, and Nicolas from Antioch, a convert to Judaism. 6 They Presented these men to the Apostles, who Prayed and Laid Their Hands on Them."
The Laying on of Hands is believed to be the unction of the Holy Spirit for authority. Remember Stephen and others already had the Holy Spirit as a Believer. This was especially for Authority why else they were already christians.
Sorry I meant to finish it but this we believe has been passed by laying on of hands on by authority for two thousand years.
Really When my son is ordained in a few years all the area pastors will attend the service They will lay hands on him and pray for his ministry we are not catholic It is part of the commissioning ceremony of our church However it does not impart any special holiness or authority on him beyond that of any other believer It is a graduation ceremony of sorts that gives my son the right to act as pastor and perform all the duties as pastor in our church much like the diploma I got entitles me to practice medicine however it imparts no special holiness or authority that is not available to any other believer
Since they already had the Holy Ghost, it was likely just an acknowledgment that they all agreed...