Reward
Reward is what a person wants to have. You cannot give a person something that that person does not want. A reward is the thing that one desires. It is a good execution of the thing toward which that person would like to advance. That person cannot be elsewhere because he or she is correcting the desire. The execution itself is the reward, as it is written, “The reward of a Mitzva (commandment)—Mitzva.”[9] The reward of a Mitzva (commandment) is to know the Metzaveh (commander). To know means to connect, as it is written, “And Adam knew his wife again” (Genesis, 4:25).
Punishment
Punishment is the opposite of reward. It is what a person neither wants nor likes. It is a degree where a person understands that progress is rewarded, and the opposite of that is the punishment. The reward and punishment are not egoistic, where a person does something and receives the reward elsewhere.
Fear
Fear means being afraid of failing to correct. Everything happens due to our effort and request of the light that reforms to come and correct us. It is possible that we did not work sufficiently in order to draw it.
Summary
The portion notes that the choice is in our hands: Either we go toward reward or toward punishment. If we learn what we need to do, and if the world learns, too, we can succeed and have both kinds of Torah, namely great lights—the written Torah and the oral Torah, the light of Hassadim and the light of Hochma that fill our souls. In this way we will rise to the degree of eternity and perfection.
[9] Mishnah, Seder Nezikin, Masechet Avot (Pirkey Avot), Chapter 4, p 2.