Stephen's indictment (7:51-53) so penetrates "uncircumcised hearts" that the Sanhedrin is furious (literally "sawn through in their hearts"; compare 5:33). They are "torn up" not with repentant sorrow for their sins but with seething anger against the preacher of repentance. They grind their teeth with such a hissing sound, such a hateful screwing of the mouth, that Stephen knows they have but one aim: to do away with him (compare Ps 34:16 LXX; 36:12 LXX). As we have seen before, when faced with the truth those in error will either accept the message or seek to silence the messenger, even permanently (Acts 4:18; 5:28, 40).