'...whom resist steadfast in the Faith, knowing that the same afflictions are accomplished in your brethren that are in the world' (I Pet. 5:9)

The most vital steadfastness of the human spirit is steadfastness in faith.  The devil hurls his arrows and his wickedness most violently at this steadfastness.  For the impure and wicked spirit knows that, when he has destroyed this steadfastness, he has enslaved the human soul forever.  Therefore, the holy apostles begged the Lord: 'Increase our faith' (Luke 17:5).  Let us also pray every day that the Lord will increase our faith, that He will strengthen and fortify it. 

Nothing in the world can be exchanged for faith in God:  neither philosphy nor learning, nor riches nor glory, nor the whole wide world with all its transitory illusions.  The devil knows this, and therefore attacks our faith, bringing doubt, making us waver, confusing our thoughts, troubling our hearts.  So, if the devil knows that faith is the most important thing, it is even more essential that we know this.  Christ came to earth for our sakes, suffered for us upon the Cross and gave to us the promise of saving faith.

from the Prologue of Ochrid, Vol. 3