“You must know that progress on the path of spiritual life differs greatly from an ordinary journey on earth. If a traveler stops on his ordinary journey, he loses nothing of the way already covered; but if a traveler on the path of virtue stops in his spiritual progress, he loses much of the virtues previously acquired …. In an ordinary journey, the further the traveler proceeds, the more tired he becomes; but on the way of spiritual life the longer a man travels, reaching forth unto those things which are before, the greater the strength and power he acquires for his further progress.”
(St Nikodemos quoted in ‘Unseen Warfare’)