Acts 6:8-11 King James Version (KJV)
8 And Stephen, full of faith and power, did great wonders and miracles among the people.
9 Then there arose certain of the synagogue, which is called the synagogue of the Libertines, and Cyrenians, and Alexandrians, and of them of Cilicia and of Asia, disputing with Stephen.
10 And they were not able to resist the wisdom and the spirit by which he spake.
11 Then they suborned men, which said, We have heard him speak blasphemous words against Moses, and against God.

Acts 6:8-11 Amplified Bible (AMP)

8 Now Stephen, full of grace (divine blessing and favor) and power (strength and ability) worked great wonders and signs (miracles) among the people.
9 However, some of those who belonged to the synagogue of the Freedmen (freed Jewish slaves), as it was called, and [of the synagogues] of the Cyrenians and of the Alexandrians and of those from Cilicia and [the province of] Asia, arose [and undertook] to debate and dispute with Stephen.
10 But they were not able to resist the intelligence and the wisdom and [the inspiration of] the Spirit with which and by Whom he spoke.
11 So they [secretly] instigated and instructed men to say, We have heard this man speak, using slanderous and abusive and blasphemous language against Moses and God.

Amplified Bible (AMP) Copyright © 1954, 1958, 1962, 1964, 1965, 1987 by The Lockman Foundation

These are my thoughts, please share yours.

8 Stephen was able to do this because of the Holy Spirit inside him. He started out as a deacon but now the Lord was using him in ways beyond that, the Lord may have us go into one position just to later have us somewhere else, it often times prepares us for what we later do for Him. Stephen being a deacon may have been used to make him ready for this.

9 These were a group of Gentile Jews, they often times had loyalty to the Emperor of Rome. They argued with Stephen, people will argue with us because they did with Christ, they will try trick us because they did with Christ and they may lie about us because they did with Christ.

10 Even though they were trying to cause trouble for Stephen, the Spirit moved over them, we can not resist the power of the Spirit.

11 They did not want to do this openly because of the numbers of the church. They also met is secret to do this with Jesus, there also may have been those of the church within this group as there were earlier with Jesus. Another corrupt trial that goes against the laws given thru Moses, the law they claim they follow they break to try to end Christians, it can not end because it is not of men so it does not die with us but it is of the Lord so it will never end because He lives.