And thus it was necessary, to confirm this, that the Holy Ghost should descend at Pentecost in tongues of fire upon those who made this assertion. (In the account of it, the descent of the Holy Ghost precedes the assembly, but the book of Acts was written much later than both events.) But the descent of the Holy Ghost too had to be proved for those who had not seen the tongues of fire (though it is not easy to understand why a tongue of fire burning above a man's head should prove that what that man is going to say will be infallibly the truth). And so arose the necessity for still more miracles and changes, raisings of the dead to life, and strikings of the living dead, and all those marvels which have been a stumbling-block to men, of which the Acts is full, and which, far from ever convincing one of the truth of the Christian doctrine, can only repel men from it.