An excerpt from the work St. Cyril of Alexandria

On the Transfiguration of the Lord, Our God and Our Savior Jesus Christ

They who are skilled in combat are pleased by the plaudits of the spectators, and urged on by the hope of rewards to the victory of their calling.  They however who aspire to divine rewards, and thirst for a share in that which is laid up for the blessed, gladly face the contests which are endured for love of Christ. They live blameless lives, not clinging to sloth, which merits no reward; neither do they yield to unworthy cowardice, but bear themselves manfully against all temptation, making light of the attacks of their persecutors; believing that to suffer for the Lord is a great gain. For they are mindful of what the Blessed Paul has said, that the sufferings of this time are not worthy to be compared with the glory to come, that shall be revealed in us (Rom. viii. 18).  

Behold therefore the all beautiful disposition of things Our Lord Jesus Christ now arranges for the profit and edification of His holy Apostles.  For He says to them:  If any man will come after me, let him deny himself, and take up his cross, and follow me.  For he that will save his life, shall lose it: and he that shall lose his life for my sake, shall find it (Mt. xvi. 24, 25).  

The precept is a salutary one, worthy of the sanctified; one which leads to heavenly glory, and conducting us to a joyful destiny.  For the will to suffer for Christ shall not go unrewarded; nay, more, it will bring us the joy of eternal life and glory.  But it was to be expected that the Disciples, who were not yet endowed with power from on high (Lk. xxiv. 49), would succumb to human foolishness and, thinking within themselves, would say: “How can anyone deny himself? How can one who has lost his life find it again?  What comparable reward can be given to those who have suffered his loss?  And also, in what kind of reward will he share?”