משה קבל תורה מסיני ומסרה ליהושע
ונביאים מסרוה לאנשי כנסת הגדולה
Mosheh received Torah at Sinai and taught it to Y’hoshuah (Joshua).
Y’hoshuah (taught it) to the elders,
the elders to the prophets,
and the prophets taught it to the men of the ‘Great Assembly’. 
What did Mosheh receive on Sinai? G-d’s Light.
What did he teach Y’hoshuah? G-d’s Light.
What did Y’hoshuah give to the elders, the elders to the prophets, and the prophets to the men of the “Great Synagogue”? G-d’s Light.
What do we receive when we learn Torah? G-d’s Light.
“From my master [the Baal Shem Tov] I received the rule that the main, essential element in occupying ourselves with Torah study and prayer is to bind ourselves to the inner, spiritual aspect of the light of the infinite, boundless G-d that exists in the letters of Torah and our prayer.” 
We receive that Light, too, by binding our hearts and minds to those who themselves have received it, back through the chain of tradition.
“How powerful is the effect of impressing the deeds of the Patriarchs [and Matriarchs] on our hearts and minds. Picturing in our mind’s eye the deeds of the righteous [tzadikim] activates our spiritual potential and brings out all the good latent in our soul. Studying the holy character of the Mussar figures of previous generations [Hasidic and other spiritual models, too] fires our imaginations and invokes a longing to emulate their deeds and ways…Remembrance leads to contemplation, contemplation leads to longing and cleaving, longing and cleaving draws the light of the tzadikim [the “righteous,” saintly ones] into the souls of their disciples.” 
Rebbe Nachman of Breslav teaches that by reciting the names of the tzaddikim, we can join our souls to theirs and receive their Light:
“The holy name of each and every Tzaddik encompasses the entire nature of that Tzaddik — all his righteousness, his Torah, his good deeds, his high qualities and accomplishments. His name is his soul and spirit. Accordingly, when we mention the name of the Tzaddik, we are drawing his holiness and merit upon ourselves, and then we too can achieve holiness and purity and return to G-d.” 
The synagogue as [בית המדרש] — “house of learning” — is where we learn Torah. The “Magen David,” unknown to the “elders,” “prophets” or “rabbis of the Talmud,” has become the symbol for us of the Torah we receive there.
No poems praise
this shield of shame.
as G-d made
bitter waters sweet
at Marah . 
The “light of the tzadikim” is the Light they received from their teachers, back to the Light Mosheh received on Sinai. The Hebrew text says that Mosheh “received” [קבל] the Light; after that, it was “taught” [מסר]. We learn Torah to bind ourselves to the Light of those who bound their Light to their teachers’ Light, back to Mosheh’s own receiving of G-d’s Light.
Even moreso is it necessary to receive the Light of our teachers, in order for a tzadik to teach Torah:
“Rabbi Mordechai of Lekhovitz said…’ The tzadik cannot say any words of the teachings unless he first links his soul to the soul of his dead teacher or to that of his teacher’s teacher. Only then is link joined to link, and the teachings flow from Mosheh to Y’hoshuah, from Y’hoshuah to the elders, and so on to the tzadik’s own teacher, and from his teacher to him’.” 
For this reason, when preparing readings for services I’ve led — especially High Holiday services — I’ve often tried to introduce each quote by mentioning the name of the rabbi who wrote or said it — including contemporary rabbis from every branch of Judaism. The sense of receiving something more than the words themselves has often been palpable.
How would you join yourself to your teacher? To your teacher’s teacher?