FOR'TITUDE, n. [L. fortitudo, from fortis, strong.] That strength or firmness of mind or soul which enables a person to encounter danger with coolness and courage, or to bear pain or adversity without murmuring, depression or despondency. Fortitude is the basis or source of genuine courage or intrepidity in danger, of patience in suffering, of forbearance under injuries, and of magnanimity in all conditions of life. We sometimes confound the effect with the cause, and use fortitude as synonymous with courage or patience; but courage is an active virtue or vice, and patience is the effect of fortitude. Fortitude is the guard and support of the other virtues.
1 Timothy 6:11
The Good Confession
11 But you, O man of God, flee these things and pursue righteousness, godliness, faith, love, fortitude, gentleness.
The strength of those who wish to acquire the virtues is as follows: if they fall, let them not lose their courage, but let them be sure to make a new beginning at their endeavor. Insofar, then, as we put all our energy into practicing the virtues, let us await the Lord, showing Him a generous resolve and calling on His aid, and without fail He will strengthen us with His mercy and bestow His Grace on us in abundance, in which case we will accomplish every good easily and without exertion. Abba Moses in The Evergetinos, Book I, Vol. III/
YOU'RE AS WEAK AS YOU ALLOW YOURSELF TO BE.