I am learning not to pass up any seemingly small event or word in order to be cleansed of my own sins.
The instant one reacts to the sins of others, one can enter into an examination of conscience. To check a reaction which could lead to sins, such as a lack of forgiveness, or a judgement, is the beginning of the purification of the mind and imagination.
This is all part of the Dark Night. Use everything. Do not let any opportunity for growth go by without reflection.
These small moments are moments of grace.
And, one may never have these same moments of grace again.
Here is a short section from Treatise on the Love of God by St. Francis de Sales:
The wife ordinarily changes her condition into that of her husband, becoming noble if he be noble, queen if he be king, duchess if he be duke. The will also changes her condition according to the love she espouses; if this be carnal she becomes carnal, if this be spiritual she is spiritual, and all the affections of desire, joy, hope, fear, grief, as children born of the marriage between love and the will, consequently receive their qualities from love. In short, Theotimus, the will is only moved by her affections, amongst which love, as the primum mobile and first affection, gives motion to all the rest, and causes all the other motions of the soul.
But it does not follow hence that the will does not also rule over love, seeing that the will only loves while willing to love, and that of many loves which present themselves she can apply herself to which she pleases, otherwise there would be no love either forbidden or commanded.
She is then mistress over her loves as a maiden over her suitors, amongst whom she may make election of which she pleases. But as after marriage she loses her liberty and of mistress becomes subject to her husband's power, remaining taken by him whom she took, so the will which at her own pleasure made election of love, after she has chosen one remains subject to it.
And as the wife is always subject to the husband whom she has chosen as long as he lives, and if he die regains her former liberty to marry another, so while a love lives in the will it reigns there, and the will is subject to its movements, but if this love die she can afterwards take another.
And again there is a liberty in the will which the wife has not, and it is that the will can reject her love at her pleasure, by applying her understanding to motives which make it displeasing, and by taking a resolution to change the object.
For thus, to make divine love live and reign in us, we kill selflove, and if we cannot entirely annihilate it at least we weaken it in such a way that though it lives yet it does not reign in us. As, on the contrary, in forsaking divine love we may adhere to that of creatures, which is the infamous adultery with which the Divine lover so often reproaches sinners.
One can learn to let love be the prime mover, as this great saint notes. All other needs and tendencies pass away.