For we have heard him say, that this Jesus of Nazareth shall destroy this place, and shall change the customs which Moses delivered us.
Note 9 at Ac 6:14: Jesus didn't come to destroy the Law but to fulfill it (Mt 5:17). He then replaced it with a better covenant (Heb 8:6-7). The Jews didn't understand this when Jesus taught on it or when Stephen spoke these same truths. Jesus did prophesy the destruction of the temple (Mt 24:1-2, Mr 13:1-2, and Lu 21:5-6) and the changing of the Mosaic customs (Mt 5:21-48 and Joh 4:21-23). However, this was not in contradiction of the Law but rather the fulfillment of it.