Mark 8:12

12 And sighing deeply in his spirit, he said, "Why does this generation demand a sign? Truly I say to you, no sign will be given to this generation!"

Mark 8:12 Meaning and Commentary

Mark 8:12

And he sighed deeply in his Spirit
In his human soul; and which shows that he had one, and was subject to grief and sorrow, and all passions and infirmities, excepting sin. This deep sigh was on account of the hardness of their hearts, the malignity of their minds, and insincerity of their intentions; who had no view to come at truth by this inquiry, but to ensnare him:

and saith, why doth this generation seek after a sign?
when so many have been shown among them, and they will not believe:

verily I say unto you, there shall no sign be given to this
generation:
such as they desired; namely, one from heaven. The Evangelist Matthew adds, "but the sign of the Prophet Jonas"; (See Gill on Matthew 16:4), (See Gill on Matthew 12:40).

Mark 8:12 In-Context

10 And immediately he got into the boat with his disciples [and] went to the district of Dalmanutha.

11 And the Pharisees came and began to argue with him, demanding from him a sign from heaven [in order to] test him.

12 And sighing deeply in his spirit, he said, "Why does this generation demand a sign? Truly I say to you, no sign will be given to this generation!"

13 And he left them, got into [the boat] again, [and] went to the other side.

14 And they had forgotten to take bread, and except [for] one loaf, they did not have [any] with them in the boat.