Why are Tzadikkim considered as if they had created themselves?
(26,3) “If you walk in My statutes, and keep My commandments, and do them.”
We can explain this posuk according to Chazal’s teaching that the greater one is, the bigger his evil inclination is. They also taught that in the future Hashem will bring the evil inclination and slaughter it in front of everybody - to the tzadikkim it will appear like a mountain, and to the wicked it will appear like a strand of hair. The Maharsha connects these two statements of Chazal and explains that since the greater one is, the bigger his evil inclination is, therefore it appears to the tzadikkim like a mountain.
Now, it says in the Midrash on the posuk “and keep My commandments, and do them” - if you observe them, I will accredit it to you as if you had made yourself. (The Hebrew words for “and do them” - ‘va’asisem osom’ - can be read ‘va’asisem atem’, which means ‘and you made yourself’) But it seems to me that only the tzaddikim to whom the evil inclination appears like a mountain, who have done a tremendous amount of work and conquered their evil inclination, can be considered as if they had given over their life completely in the service of Hashem. Therefore they are paid measure for measure, and it is considered as if they had created themselves. But these whose evil inclination is not so great, and who cannot be considered as if they had given over their lives, are not considered as if they had made themselves.
Therefore the posuk says, “If you walk in My statutes”, which Rashi explains means that if you will toil in the study of Torah, and nevertheless “keep My commandments”, and overcome the increased evil inclination, then “you shall do them” - I will accredit to you as if you had made yourself. But if you do not toil in the study of Torah, then even if you keep My commandments it will not be considered as if you had made yourself since your evil inclination is not so great.
When does the rule ‘there is no reward for mitzvos in this world’ not apply?
(26,3) “If you walk in My statutes, and keep My commandments, and do them. I will give your rains in their time…”
The posuk says, “I will give your rains in their time”, and Chazal teach us that “in their time” means Shabbos night, when people do not usually go out. But we can also explain the posuk according to the teaching of Chazal that there is no reward for mitzvos in this world. The Maharsha explains that the reason is because a person may abandon his righteous ways, and Chazal teach that one who regrets his earlier good deeds retroactively destroys all his merits. Therefore, he is not paid a reward in this world.
But this is possible only for someone who is not involved in learning Torah, but someone who is involved in learning Torah is saved from sin, as Chazal expounded the posuk in Mishlei 2:11 “Thought shall watch over you” - the Torah shall guard you. And this is especially true of a Torah sage who learns Torah all the way through to the halachah, and about whom Chazal teach that when he comes to a crossroads (to a place of great danger) he is saved from everything. If so, such a person will never in the future sin and therefore he deserves to be rewarded in this world.
Now, a Torah sage who learns all the way through to the halachah is rectifying and clarifying the mitzvos in order to establish the halachah. One who does not do this only has the reward of his learning, but the Torah sage who is establishing the halachah has two merits - his learning and his rectification and clarification of the mitzvah.
Acccording to these teachings, this is what these posukim mean: “If you walk in My statutes” - if you toil in the study of the Torah (as Rashi explains), and also if you “keep My commandments, and do them” - rectify and clarify the mitzvos (the word ‘asiyah’ (doing) can also mean rectification), then no sin will occur through you and thus I will give you your reward immediately in this world -“I will give your rains in their time”. All material benefits are included in the word for rain - ‘geshem’ (the word ‘gashmiyus’ means materialism), and thus the posuk means that I will give you all your material needs in their time, immediately after the mitzvah.