Musar zu Dewarim 30:2

In explanation of repentance and its principles
Among the good things which God, may He be blessed, has bestowed upon His creations is the path which He prepared for them to ascend from the baseness of their actions, to escape the trap of their inequities, to hold their souls back from destruction and to remove His anger from upon them. Because of His goodness and uprightness, He has taught them and warned them to return to Him when they sin against Him - for He understands their nature, as it is stated (Psalms 25:8), "Good and upright is the Lord; therefore He shows sinners the way." [Even] if they greatly sin and rebel and act like treacherous betrayers - He does not close the doors of repentance to them, as it is stated (Isaiah 31:6), "Return, to Him to whom they have been so shamefully false." It is [also] stated (Jeremiah 3:22), "Turn back, O rebellious children, I will heal your afflictions." We are warned about repentance in several places in the Torah. It is explained that repentance is accepted even when the sinner repents because of his many troubles - how much more so [will it be accepted] if he returns because of fear or love of God - as it is stated (Deuteronomy 4:30), "When you are in distress because all these things have befallen you and, in the end, return to the Lord your God and obey Him." It is explained in the Torah that God will help those who repent beyond what their natural ability would allow; and that He renews a pure spirit within them, to reach great heights in His love - as it is stated (Deuteronomy 30:2), "And you return to the Lord your God, and you and your children heed His command with all your heart and soul, just as I enjoin upon you this day." Further, it is stated about the body of the matter (Deuteronomy 30:6), "Then the Lord, your God, will circumcise your heart and the hearts of your offspring," to acquire love for Him. And the Prophets and Writings constantly speak on the subject of repentance, such that the principles of repentance are all explained in their words, as will be explained.

It was a great kindness that the Holy One, Blessed be He, did for mankind when he established a way for wrong-doers and sinners to flee from darkness to light, and did not close the doors of repentance to them, even if they had sinned greatly, as it is said, "Return, ye backsliding children, I will heal your backslidings" (Jer. 3:22). And repentance is accepted by God even if the sinner repents because of his great misfortunes; all the more so if he repents because of reverence and love of God. As it is said, "In thy distress, when all these things are come upon thee, in the end of days thou will return to the Lord thy God; and hearken unto His voice" (Deut. 4:30). And the Holy One, Blessed be He, helps penitents to repent even in matters which the strength of a man cannot attain, and he renews within them a pure spirit so that they may achieve the elements of repentance. As it is said, "And shalt return unto the Lord thy God, and hearken to His voice according to all that I command thee this day, thou and thy children, with all thy heart, and with all thy soul" (Deut. 30:2). And further, at the end of that passage, "And the Lord will circumcise thy heart, and the heart of thy seed, to love the Lord thy God with all thy heart" (Deut. 30:6). What this means is that in that thing which is not within your power to attain, the Holy One, Blessed be He, will circumcise your heart and give you the strength to do it.

In sum: One must take care to fulfill the words of the Torah, both those things between man and his Maker and those things between man and his neighbor. For they are all the word of the L-rd, as it is written (Devarim 32:46-47): "…which you are to command your children to keep and to do — all the words of this Torah. For it is not an empty thing for you. For it is your life." For just as with the body there is life in every limb, and all [of the limbs] are required by it, so, in every mitzvah there is life for a man's soul and all [the mitzvoth] are required by it. This is the intent of Koheleth 12:13: "The end of the matter — all has been heard. Fear G-d and keep His mitzvoth. For this is the whole man." That is, through the fear of G-d, not to transgress any negative commandment and to fulfill all of His positive commandments — this is the whole man. That is, then the man is called "complete," which is not so if some mitzvah is minor in his eyes, G-d forbid, in which instance he is lacking in his soul.