5 The war will be bitter and without respite on the part of those who wage it. That as it goes on harder trials than those which you have hitherto known await you is possible and even probable. Common prudence calls on each of you to prepare for them. And this you will do simply, valiantly, and full of confidence, sure that however fiercely the fight may rage, victory will in the end remain in your hands.
Source: Une Fois Encore (Vatican.va)