Toil and pain vanishes over time

Venerable John Climacus ~ The Ladder of Divine Ascent
Step 4 ~ On Obedience

¶4. The beginning of the mortification both of the soul’s desire and of the bodily members is much hard work. The middle is sometimes laborious and sometimes not laborious. But the end is insensibility and insusceptibility to toil and pain. Only when he sees himself doing his own will does this blessed living corpse feel sorry and sick at heart; and he fears the responsibility of using his own judgment.