Francois Fenelon preaches about the importance of tolerance and understanding towards the imperfections of others. He emphasizes the need to bear with the unmistakable defects of others, refrain from condemning doubtful ones, and not allow these imperfections to cause division. Fenelon highlights that perfection is easily tolerant of imperfections, urging individuals to patiently wait for God to address these weaknesses in others. He encourages self-correction and advises to approach the correction of others with humility and sensitivity, aiming to strengthen relationships rather than weaken them.

LETTER XXIV. Imperfection only is intolerant of imperfection. It has seemed to me that you have need of more enlargedness of heart in relation to the defects of others. I know that you cannot help seeing them when they come before you, nor prevent the opinions you involuntarily form concerning the motives of some of those about you. You cannot even get rid of a certain degree of trouble which these things cause you. It will be enough if you are willing to bear with those defects which are unmistakable, refrain from condemning those which are doubtful, and not suffer yourself to be so afflicted by them as to cause a coolness of feeling between you. Perfection is easily tolerant of the imperfections of others; it becomes all things to all men. We must not be surprised at the greatest defects in good souls, and must quietly let them alone until God gives the signal of gradual removal; otherwise we shall pull up the wheat with the tares. God leaves, in the most advanced souls, certain weaknesses entirely disproportioned to their eminent state. As workmen, in excavating the soil from a field, leave certain pillars of earth which indicate the original level of the surface, and serve to measure the amount of material removed--God, in the same way, leaves pillars of testimony to the extent of his work in the most pious souls. Such persons must labor, each one in his degree, for his own correction, and you must labor to bear with their weaknesses. You know from experience the bitterness of the work of correction; strive then to find means to make it less bitter to others. You have not an eager zeal to correct, but a sensitiveness that easily shuts up your heart. I pray you more than ever not to spare my faults. If you should think you see one, which is not really there, there is no harm done; if I find that your counsel wounds me, my sensitiveness demonstrates that you have discovered a sore spot; but if not, you will have done me an excellent kindness in exercising my humility, and accustoming me to reproof. I ought to be more lowly than others in proportion as I am higher in position, and God demands of me a more absolute death to everything. I need this simplicity, and I trust it will be the means of cementing rather than of weakening our attachment.