פירוש על דברים 5:30

למען תחיו וטוב לכם, in order that you will live enduringly in a good and happy frame of mind.

בכל הדרך…למען תחיון, "all along the way …in order that you may live, etc." The meaning of תחיון וטוב לכם והארכתם means "long life on earth." The additional promise of וטוב לכם refers to the good which they will experience in the hereafter. The meaning of the word והארכתם ימים בארץ is that the Israelites will not ever be exiled from their land.

והארכתם ימים בארץ אשר תירשון, so that you will acquire “long life” in a world which is itself one of unlimited duration.

According to the view of Rabbi Yaakov in Kidushin 39 that there is no reward in this life for the commandments we observe, it appears that even this Rabbi concedes that if someone is a totally righteous person who has observed all the commandments which it is possible for him to observe, he will experience some reward even in this life. The kind of person who was the subject of Rabbi Yaakov's statement is the one whose credits outweigh his debits. The Talmud on the folio quoted supports Rabbi Yaakov's view and adopts it as normative.

From the above you may conclude that only people who are guilty of sins,- though these are outweighed by their good deeds-qualify for the statement in the Talmud that such people will experience afflictions in this life. The reason for this is so that such people will not have to experience afflictions in the hereafter for unatoned sins. When a person is not guilty of such sins he obviously will enjoy the benefits this life has to offer. The Torah alludes to this when writing that "if you walk along the whole way" which G'd has commanded. Such a person will enjoy both the hereafter and the good life in this world. The Torah underlines this by not just writing: "you will enjoy long life," but by writing: "you will enjoy long life on the land you are going to inherit." Had the Torah not added these extra words I would have interpreted the reference to long life as referring to the kind of life which is long by definition, i.e. the hereafter.