Think of whatever you have accomplished in your life that was/is a single-minded pursuit: rearing children, getting out of debt, converting vision into reality, establishing something new, improving an existing venue, making widgets. Did you know at the beginning what you know now? Can you point to courage gained along the way by simply never giving up?
Whatever the cause/endeavor,it seems courage is what happens when we apply the devotion of our heart. God, when invited, can take care of the length and breadth of the mission.
So...want courage? Choose your helpful cause, apply your devotion one day at a time, invite God into the mix, and watch a beautiful thing happen.