Likutei Moharan 30:2/ליקוטי מוהר"ן ל׳:ב׳

12. Each person must seek out a suitable teacher such as this, one who can elucidate and give him to understand such a great and lofty insight, namely, perceptions of Godliness. For this is something which requires a very, very great rabbi; one who can explain a great insight as this through <a lesser and lower insight>, as mentioned, so that people lacking [in spiritual perception] can understand it.

2In addition, the more one is lacking [in spiritual perception] and the further one is from the Holy One, the greater the rabbi one needs. Thus, we find that when the Jewish people were on a very low level, when they were trapped in the Forty-Nine Gates of Impurity in Egypt, they required a great master, a great and awesome teacher—namely Moshe Rabbeinu .

3For the more lacking and removed one is, the more one needs a great teacher. He has to be an educator of such quality that he is able <to imbue, elucidate and> enclothe an insight as lofty as this—i.e., a perception of the Holy One—to one as lacking and distant as he. For the sicker the patient, the greater <and more expert> the doctor he requires.

4Therefore, a person should not say: “It is enough for me to be a follower of a distinguished, God-fearing individual, even if he is not so outstanding. Would that I first be like him.” Do not say this. On the contrary, to the degree that a person knows inside himself the extent of his unworthiness and his remoteness from the Holy One—commensurate with what each and every person knows in his soul, as well as his great distance which he himself recognizes—he has to seek a very, very great healer for his soul, indeed, the greatest one. That is, he has to persistently and constantly request that he be found worthy of drawing closer to the very, very great master. For the more one is lacking [in spiritual perception], the greater the teacher he needs, as above.