Twice a day those who serve G-d accept His sovereignty, remember the Exodus from Egypt, and declare their unique love for G-d. A close look at the passage of the Shema will reveal another important principle that can be found peeping out from among the cracks of the Shema.
“And you shall not be led astray by your hearts and by your eyes” [Bamidbar 15:39]. The author of the Sefer Hachinuch lists this as a negative mitzva:
“We have been commanded not to let our thoughts go to opinions which are the opposite of the ideas on which the Torah is based, since this can lead to an error… And similarly, a man is not allowed to follow what he sees with his eyes… Not to pursue the lusts of this world… And that is what the sages taught: ‘After your hearts’ means apostasy, and ‘after your eyes’ means illicit sex.”
The Torah warns us against two different situations.
“After your hearts means apostasy.” The unlimited power of the heart as a source of our thoughts and understanding might at times lead a person to realms which he does not want to reach. We must not entertain “opinions which are the opposite of the ideas on which the Torah is based.” There is a very fine line that separates a person’s ability and obligation to study all the available subjects and analyze them in depth from the danger that as a result of the deep study we might become confused about the main principles of our faith. The author of Sefer Hachinuch adds, “A person should not focus his thoughts on matters which might bring him to abandon the path of our holy Torah and move over to ideas which are shocking and heretical.” The Torah demands that a person view the opinions to which he is exposed in an honest way, and to understand that at times the result of deep study and an open mind can take him to places where he did not want to go. The Torah is afraid that we will lose control and not be able to maintain a proper balance.
“After your eyes means illicit sex.” What we see with our eyes can also make us lose control. A person can convince himself that what he sees will never take him astray, that he always remains the master, in control. However, the Torah warns us to beware of exaggerated self-confidence. At times, “the eye sees and the heart begins to lust,” and the result is “being drawn after physical lusts and pleasure and constantly being busy with them.” At times a person might lose all control of his inclinations. He might convince himself that his eyes will not lead him to sin, but this is not so. The process of wearing his defenses down begins with his uncontrolled exposure to the pleasures of the world, neither gently or modestly.
We are used to thinking that we have the power to control our inclinations and our thoughts. This mitzva of “do not be led astray” is trying to warn us that our ability to keep control depends on where we were born and raised. In order for us to develop and grow properly, we must make sure that the initial status is the proper one. We must start out without any illicit sex or apostasy.
What are the limits of this mitzva? How can a man know when he oversteps the boundary? This requires us to accomplish difficult and infinite labor. This can be done, it is necessary to open up the boundaries and keep them closed at one and the same time.