Acts 7:51-55
Acts 7:51 (KJB)
Ye stiffnecked and uncircumcised in heart and ears, ye do always resist the Holy Ghost: as your fathers did, so do ye.
Stiffnecked - Inflexibly obstinate, stubborn, or unyielding
Resist - Oppose or falling against
Here Stephen begins the part of His dialogue which is going to lead to him being stoned by these rank unbelievers. He may not have been finished with his narrative and there was probably some mumbling going on and that is when Stephen seemed to abruptly stop the historical narrative he was speaking. He saw the Sanhedrin as being unyielding in their understanding of biblical things and they were still in total opposition against the true Gospel. This is why Stephen accused them of resisting the Holy Ghost. (John 16:13 KJV) Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will show you things to come. Jesus called the Holy Spirit, the Spirit of truth and it was the truth that the Holy Spirit was bringing the Sanhedrin through the ministry of Stephen but they remained steadfast in opposition. Deuteronomy 10 calls for them to circumcise the heart and be no more stiff necked. (Deu 10:16 KJV) Circumcise therefore the foreskin of your heart, and be no more stiffnecked. These leaders were still in opposition to Christ and all His followers and that is why they continually turned a deaf ear to the truth. He then compares them to the earlier fathers of Israel who had opposed all the prophets which God sent to them throughout their history. What they did not know was that as Judah was sent to Babylon and Israel to Assyria, in 37 years they too would be scattered to the four winds as a judgment against their hatred of the Gospel.
Acts 7:52 (KJB)
Which of the prophets have not your fathers persecuted? and they have slain them which showed before of the coming of the Just One; of whom ye have been now the betrayers and murderers:
Stephen then asks a pointed question which can only have one answer. Notice how Stephen uses the word “your” and not the word “the” before fathers. He is making a connection between their attitudes and the ungodly, murdering attitudes of their predecessors. They had heard the prophets which God sent them but rejected the messages and had them put to death. All the prophets which God sent in years past were pointing to the coming of the Lord Jesus Christ, one such prophet was Isaiah who according to tradition was sawed in half in a hollow tree trunk. Now Stephen makes an accusation which will make them boil with rage. He accuses them of being the betrayer and murderer of the Just One, and they know full well that he is speaking of Christ whom they had crucified. Judas had betrayed Christ but Stephen sees them as one in mind because they gave Judas money for the betrayal, and they were the same ones who called for the murder of Christ.
Acts 7:53 (KJB)
Who have received the law by the disposition of angels, and have not kept it.
Disposition - Ordinance, arrangement, or direction
When the Lord gave Moses the law on Sinai, He was accompanied by thousands of angels. (Psa 68:17 KJV) The chariots of God are twenty thousand, even thousands of angels: the Lord is among them, as in Sinai, in the holy place. Here Stephen tells them that they received the law which was given by God on Sinai but in the hardness of their hearts, they have not kept the law but instead had abrogated it and rewrote many parts of it to fit their evil and greedy lifestyles. It was also written in such a way that they were able to control the people by it. This rewrite is called the “Talmud” which held more authority than the Scriptures did to these false teachers.
Acts 7:54 (KJB)
When they heard these things, they were cut to the heart, and they gnashed on him with their teeth.
Gnashed on him with their teeth - (Job 16:9 KJV) He teareth me in his wrath, who hateth me: he gnasheth upon me with his teeth; mine enemy sharpeneth his eyes upon me.  A term which means anger or in this case an angry reaction to Stephen’s speech.
As soon as they heard the accusations and the comparisons that Stephen was making with their earlier fathers who had killed the prophets, they were cut to the heart, that is, it was a like a saw went through their hearts when they heard it. They could not refute the charge but in their anger, they were about to commit another murder, since murder was already in their heart, it was now going to be physically manifested. This was another proof of how they resisted the truth that the Holy Spirit had given them through Stephen.
Acts 7:55 (KJB)
But he, being full of the Holy Ghost, looked up stedfastly into heaven, and saw the glory of God, and Jesus standing on the right hand of God,
Full - Complete or filled up
Steadfastly - Look intently or fix one’s eyes
Stephen was completely filled with the Holy Ghost and being in the Spirit like that he had fixed his gaze upon Heaven. Stephen probably knew at this time that his home going was imminent. He had seen something that no one else had ever seen and lived. Stephen had seen the Glory of God which would normally consume a person but he was being qualified by God to see this Glory. He not only saw the Glory of God in Heaven but he saw the Lord Jesus Christ standing and not sitting at the right hand of God. This is telling us that Jesus had rose from His throne to soon welcome the first martyr into Heaven. This was a special occasion because the Scriptures see Jesus as sitting at the right hand of God. (Luke 22:69 KJV) Hereafter shall the Son of man sit on the right hand of the power of God. This was probably the greatest honor ever paid to a Christian to see the Lord Jesus Christ standing. It also shows us that when we keep our testimony and do not let it be compromised by the world’s teachings or false religions, it pleases the Lord and is sanctioned by Him. The standing of Jesus in glory is approval of those who will not compromise their testimony to the point of death. It seems this act of Jesus standing and the Christians keeping a strong, unmovable testimony are tied together.