Mahayana scholasticism typically divides kshanti into three grades of difficulty: patience with harm done by others, patience with the ordinary sufferings of illness, weather and physical hardship, and the hardest of the three by most commentators' reckoning, patience with a difficult or counterintuitive teaching, the willingness to sit with a doctrine such as emptiness, shunyata, before it is fully understood rather than rejecting it out of discomfort.
Shantideva devotes an entire chapter of the Bodhicaryavatara to the perfection, and his argument against anger at harm is characteristically direct: an enemy who harms you acts from causes and conditions, itself a form of suffering, so that anger at the person mistakes a symptom for a chosen cruelty, and even physical pain, examined closely, is a series of momentary sensations that dissolve on inspection rather than a solid thing to resent. The perfection sits third in the sequence deliberately, following the ethical foundation of sila, because Mahayana texts treat patience as what makes sustained ethical conduct possible under provocation rather than only in comfortable circumstances; a discipline that holds only when untested is not yet the perfection being cultivated.