Albert Barnes Commentary Acts 4:15-18

"But when they had commanded them to go aside out of the council, they conferred among themselves, saying, What shall we do to these men? for that indeed a notable miracle hath been wrought through them, is manifest to all that dwell in Jerusalem; and we cannot deny it. But that it spread no further among the people, let us threaten them, that they speak henceforth to no man in this name. And they called them, and charged them not to speak at all nor teach in the name of Jesus." — Acts 4:15-18 (ASV)

What shall we do to these men? The object they had in view was evidently to prevent their preaching. The miracle was performed and was believed by the people to have been performed. This, they could not expect to successfully deny. Their only object, therefore, was to prevent the apostles from making the use of it that they foresaw, to convince the people that Jesus was the Messiah.

The question, therefore, was how they should prevent this: whether by putting them to death, by imprisoning them, or by scourging them, or by simply exerting their authority and forbidding them. From the former actions they were deterred, doubtless by fear of the multitude. Therefore, they adopted the latter course and seemed to suppose that the mere exertion of their authority would be sufficient to deter them from this in the future.

The council (in Greek, the Sanhedrin) was composed of seventy-one or seventy-two persons and was entrusted with the principal affairs of the nation. It was a body of vast influence and power; hence, they supposed that their command might be sufficient to restrain ignorant Galileans from speaking.

Before this same body, and probably the same men, our Savior was arraigned and by them condemned before he was delivered to the Roman governor (Matthew 26:59 and following). And before this same body, and in the presence of the same men, Peter had just before denied his Lord (Matthew 26:70 and following). The fact that the disciples had fled on a former occasion, and that Peter had denied his Savior, may have led them to believe that the apostles would be terrified by their threats and deterred from preaching publicly in the name of Jesus.

A notable miracle. A known, undeniable miracle.

That it spread. This means that the knowledge of it was not to spread among them any further.

Let us straitly threaten them. In Greek, this is literally Let us threaten them with a threat. This is a Hebraism, expressing intensity, certainty, and so on. The threat was a command (Acts 4:18) not to teach, implying their displeasure if they did.

This threat, however, was not effective. On the next occasion, which occurred soon after (Acts 5:40), they added beating to their threats in order to deter them from preaching in the name of Jesus.

The phrase out of the council means "to withdraw from."