Musar su Ecclesiaste 7:20

And now understand - listen to this, for it is a great principle. It is true that there are righteous people who sometimes stumble into sin - like the matter that is stated (Ecclesiastes 7:20), "For there is no man that is righteous on earth, who does good and does not sin." However they conquer their impulses from in front of them. And if they do fall to sin once, they will not repeat it. [Rather] they will have it taken away from in front of them and repent. However anyone who is not careful of a particular sin and does not take upon himself to guard against it - even if it is from the light ones [and] even though he guards himself against all of the [other] transgressions of the Torah - the Sages of Israel call a habitual sinner (mumar) about one thing (Chullin 4b); he is counted with the sinners, and his sin is too great to bear. For surely if a slave said to his master, "I will do everything you tell me except for one thing," he has already broken his master's yoke from upon himself and will do what is proper in his [own] eyes. And this whole matter is stated [in] (Deuteronomy 27:26), "Cursed be he who will not uphold the words of this Torah, to do them" - the explanation of the matter is that he does not accept upon himself to fulfill all of the words of the Torah, from beginning to end. And what indicates this [is the phrase], "who will not uphold [...] to do" - and it did not state, "who will not do them."

But there are many people for which the light of repentance is obstructed. For since they are innocent and pure in their eyes, they do not avail themselves of the rectification of their actions - as it appears to them that they are [already] rectified, whereas they sin much to God. Is it not written (Ecclesiastes 7:20), "For there is no righteous man on earth who does what is best and doesn’t sin?" But since these people belittle iniquities, they do not feel or understand it; or when they are made known of their sins, it is afterwards forgotten from their hearts. And behold they are like a sick person who does not feel his sickness, so he does not think of a cure. So his sickness constantly gets worse, until he is not able to be healed. And sometimes the reason for this is from their lack of understanding. For they do not go to seek God and do not want to know His ways. Therefore they do not regularly [visit] the doors of the sages and the [Torah] students, like the matter is stated (Proverbs 15:12), "The scoffer dislikes being reproved; he will not resort to the wise."

He will lust that all other human beings will likewise do the same. And he will be pained and grieve when they diminish in this honor. All the more so, will he be pained of what he himself diminishes, whether accidentally, unwittingly or due to natural weakness, which makes it difficult for him to guard himself from sin at all times, as scripture writes: "for there is no righteous man on earth who does good and sins not" (Kohelet 7:20).