There is no doubt that the actions of ISIS are designed to amplify their power and the threat that they pose. That helps them recruit. That adds in the twisted thoughts of some young person that they might want to have carry out an action that somehow they're part of a larger movement.
Should doubt knock at your doorway, just say to those skeptical, disturbing, rebellious thoughts: "I propose to stay with my faith, with the faith of my people."
A vocation makes us unthinking; that is its greatest blessing. For it is a bulwark behind which we are permitted to withdraw whencommonplace doubts and cares assail us.
The probability that we face global warming caused by fossil fuels is now so overwhelming that it is legitimate to doubt the motives of those who deny it
I have had so many evidences of [God's] direction, so many instances when I have been controlled by some other power than my own will, that I cannot doubt that this power comes from above.
A man was meant to be doubtful about himself, but undoubting about the truth; this has been reversed. Nowadays the part of a man that a man does assert is exactly the part he ought not to assert - himself. The part he doubts is exactly the part he ought not to doubt - the Divine Reason.