Musar к Мишлей 7:3

When a man is born he is in his body and in his wisdom weaker than all other creatures. For all creatures from the very day they were born can walk, eat and help themselves. But man requires much in his physical needs. And he needs even more correction in his soul, to adjust his wisdom and to understand the good paths. For man at his beginning, without someone to teach him, conducts himself like one of the cattle, but his heart is like a tablet which is ready to be written upon. If this tablet is in the hands of a fool then he will scribble upon it until he spoils the tablet and it has no further worth. But the wise man will write upon it the correct order of his affairs and his needs and his obligations. And from the information written on this tablet he will be enabled to feed and support his children and attain great worth. Such is a heart of man! The fools draw upon it drawings of falsehood and write upon it engravings of wrong-doing. And they fill their hearts with thoughts of folly and emptiness while the intelligent people write upon the tablet of their hearts, the writing of God, which is the foundation of the Torah and the Commandments, the wisdom of attaining noble qualities, until their souls shine like the radiance of the firmament. And this was the intention and meaning of Solomon when he said: "Bind them upon thy fingers, write them upon the table of thy heart" (Prov. 7:3).

It also states, “Write them upon the tablet of your heart” (Mishlei 7:3). A person must be well rounded in his learning. That is, he must be fluent in all four levels of interpretation: peshat [the plain meaning], remez [hints such as numerical values], derush [application of the various rules of interpretation] and sod [the esoteric meaning]. The acronym for these four levels is the word pardes [the “orchard”]. If one fails to study even one of these levels one must return in another incarnation to complete the task.