Charity “is not ambitious,” because love does not continually seek its own advancement, honor, or recognition. Ambition desires to rise above others and to secure praise for itself; charity forgets itself in seeking the good of another. Thus the charitable soul becomes less occupied with defending its own importance. It no longer measures every circumstance according to personal gain or loss, but learns gradually to love what is good simply because it is good. (St. John Chrysostom)

“Seeketh not her own.” This does not mean that charity neglects all care for itself, but that it refuses to make self-love its governing principle. Augustine teaches that the root of sin lies in the soul curved inward upon itself. Pride seeks its own advantage first; charity seeks God and neighbor. Therefore the soul grows in charity precisely as it is freed from slavery to its own will. The more a man clings to himself, the more restless he becomes; the more he gives himself in love, the more he finds peace. (St. Augustine)

“Is not provoked to anger.” The Apostle does not say that charity never feels the movement of anger, but that it is not ruled by it. For even the saints experienced sorrow and righteous indignation; yet they did not surrender themselves to bitterness or hatred. Charity restrains the sudden impulses of the heart and refuses to nourish resentment. It is easy to become inflamed by injury when the soul is full of pride; but humility softens anger because it remembers its own weakness before God. (St. John Chrysostom)

“Thinketh no evil.” Charity does not delight in suspicion, nor is it eager to interpret another’s actions in the worst possible light. There are some who carry hidden bitterness within themselves and therefore judge all things harshly. But charity inclines the soul toward mercy. Augustine often warns that the heart easily becomes darkened when it continually feeds upon accusations and hostile judgments. Charity does not ignore sin, but neither does it eagerly dwell upon the faults of others. Rather, it seeks whenever possible to excuse, to heal, and to preserve peace. For the charitable soul would rather suffer wrong itself than hastily condemn another unjustly. (St. Augustine)

Sources: St. John Chrysostom, Homilies on First Corinthians, Homily 33; St. Augustine, sermons and writings on charity, humility, self-love, and judgment.