This ignorance of the disciples proceeds not so much from slowness of understanding as from affection, for since they were yet carnal and ignorant of the mystery of the cross, they could not believe that He whom they thought to be really God would suffer death. And because they were often accustomed to hear Him speak by figure, they thought that He meant figuratively something else, by what He said of His betrayal.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).