John Chrysostom

For the signs He wrought were not in order to move them, for He knew that they were hard as stone, but for the profit of others. Or because they had not received it when He had given them a sign such as they now desired. And a sign was given them, when by their own punishment they learned His power. This He alludes to when He says, No sign shall he given it. As much as to say; I have shewn you many mercies; yet none of these has brought you to honour My power, which you will then know when you shall behold your city thrown down upon the ground in punishment. In the mean time He brings in a saying concerning the Resurrection which they should after understand by those things that they should suffer; saying, Except the sign of the Prophet Jonas. For verily His Cross would not have been believed, unless it had had signs to testify to it. But if that were not believed, truly the Resurrection would not have been believed. For this reason also He calls this a sign, and brings forward a figure thereof, that the verity itself may be believed. It follows, As Jonas was three days and three nights in the belly of the whale,