'Fidelity' in the Bible

“Woe to you, [self-righteous] scribes and Pharisees, hypocrites! For you give a tenth (tithe) of your mint and dill and cumin [focusing on minor matters], and have neglected the weightier [more important moral and spiritual] provisions of the Law: justice and mercy and faithfulness; but these are the [primary] things you ought to have done without neglecting the others.

Then said Jesus, "This night all of you will stumble and fail in your fidelity to me; for it is written, 'I will strike the Shepherd, and the sheep of the flock will be scattered in all directions.'