Thomas.

John 20:25-28
So the other disciples told him, "We have seen the Lord!" But he replied, "Unless I see the nail marks in His hands, and put my finger where the nails have been, and put my hand into His side, I will never believe." . . .

we know not.

John 15:12
This is My commandment, that you love one another as I have loved you.

Mark 8:17, 18
Aware of their conversation, Jesus asked them, "Why are you debating about having no bread? Do you still not see or understand? Do you have such hard hearts? . . .

Mark 9:19
"O unbelieving generation!" Jesus replied. "How long must I remain with you? How long must I put up with you? Bring the boy to Me."

Luke 24:25
Then Jesus said to them, "O foolish ones, how slow are your hearts to believe all that the prophets have spoken.

Hebrews 5:11, 12
We have much to say about this, but it is hard to explain, because you are dull of hearing. . . .