The saint didn't oppose preaching the truth, or correcting others, but he thought it should be done with gentleness.
Many have argued that priests need to “preach the truth” by calling out evil in the world and condemning individuals to Hell for their public sins.
This style of preaching often leads to harsh rebukes during homilies, calling people derogatory names, while pointing out the error of their ways.
St. Francis de Sales was a strong advocate against harsh preaching, though he wasn’t against speaking the truth.
He firmly believed that the truth needed to be spoken, and on occasion you may even have to rebuke someone who is leading others astray.
However, his approach was entirely different than many priests in his own time.
In the 19th-century collection, A Year with the Saints, St. Francis de Sales explains his approach to fraternal correction.
Whoever has the charge of others ought not hesitate to resist and correct the vices of those who depend on him, or even to oppose their sentiments when need requires it—-always, however, with mildness and peace, especially when he has to enunciate any truths difficult to receive. Such truths must first be heated by a burning fire of charity, which will take away all their sharpness; otherwise, they will be sour fruit, better calculated to cause disease than to give nourishment. Nothing is more bitter than walnut-bark when it is green; but when made into a preserve, it is very sweet and exceedingly wholesome. So reproof, which is very bitter in its nature, heated at the fire of charity and sweetened by amiability, becomes itself pleasing and delicious. And when truth uttered by the tongue is destitute of sweetness, it is a sign that the heart is wanting in true charity.
This same truth in expressed in a popular quote from St. Francis de Sales.
Interestingly, speaking the truth with gentleness was a struggle for St. Francis de Sales.
He possessed a very animated spirit and would often be tempted to lash out in anger. It took much strength and courage to control his temper and to rebuke others with gentleness.
Furthermore, he saw zeal and anger to be a deadly combination.
There are persons who believe that no one can have great zeal without great anger, thinking they can accomplish nothing unless they spoil everything. On the contrary, true zeal rarely makes use of anger. Just as we do not apply the knife and flame to sick men unless they cannot be helped otherwise, so too holy zeal does not employ anger except in extreme necessity.
Being angry because of an injustice is not a sin, but that anger needs to be directed properly.
Otherwise, as St. Francis de Sales says, “Bitter, harsh, presumptuous, and insolent minds, serving their own inclinations, moods, dislikes, and arrogance, would cover their own injustice with a mantle of zeal.”
Above all, priests should speak the truth, but harsh preaching shouldn’t be the norm, lest it become “sour fruit” and “cause disease” rather than “nourishment.”