NET
8 Now immediately, when Jesus realized in his spirit that they were contemplating such thoughts, he said to them, “Why are you thinking such things in your hearts?
Darby
8 And straightway Jesus, knowing in his spirit that they are reasoning thus within themselves, said to them, Why reason ye these things in your hearts?
KJV
8 And immediately when Jesus perceived in his spirit that they so reasoned within themselves, he said unto them, “Why reason ye these things in your hearts?”