On the other hand, if one studies [Torah] and performs a commandment with love alone in order to cleave to Him through [the study of] His Torah and [the performance of] His commandments, then this is not termed “service of a servant,”

מַה שֶּׁאֵין כֵּן אִם לוֹמֵד וּמְקַיֵּים הַמִּצְוָה בְּאַהֲבָה לְבַדָּהּ, כְּדֵי לְדָבְקָה בוֹ עַל יְדֵי תּוֹרָתוֹ וּמִצְוֹתָיו – אֵינָהּ נִקְרֵאת בְּשֵׁם עֲבוֹדַת הָעֶבֶד,

whereas the Torah has declared: “You shall serve (vaavadetem) the L-rd your G-d….”9 This verb is cognate with the noun eved (“servant”) and thus signifies service motivated by the fear and awe of G-d, and it is likewise written: “Him shall you serve (taavodu)….”10

וְהַתּוֹרָה אָמְרָה: "וַעֲבַדְתֶּם אֵת ה' אֱלֹהֵיכֶם וְגוֹ'", "וְאוֹתוֹ תַעֲבוֹדוּ וְגוֹ'";

As explained in the Zohar (Parashat Behar): “Just like the ox on which one first places a yoke in order to make it useful to the world…so, too, must a human being first of all submit to the yoke of the Kingdom of Heaven…and only then engage in divine service, and if this [submission] is not found in him, holiness cannot rest within him….’’11

וּכְמוֹ שֶׁכָּתוּב בַּזֹּהַר [פָּרָשַׁת בְּהַר]: "כְּהַאי תּוֹרָא דְּיָהֲבִין עֲלֵיהּ עוֹל בְּקַדְמֵיתָא בְּגִין לְאַפָּקָא מִינֵּיהּ טַב לְעָלְמָא כוּ', הָכֵי נַמֵי אִצְטְרִיךְ לְבַר נַשׁ לְקַבָּלָא עֲלֵיהּ עוֹל מַלְכוּת שָׁמַיִם בְּקַדְמֵיתָא כוּ', וְאִי הַאי לָא אִשְׁתְּכַח גַּבֵּיהּ – לָא שַׁרְיָא בֵּיהּ קְדוּשָּׁה כוּ'";

And (in Raaya Mehemna, ibid. 111b) it is written that every man must in his divine service belong to two categories and levels,

[וּבְרַעְיָא מְהֵימְנָא שָׁם דַּף קי"א עַמּוּד ב'] שֶׁכָּל אָדָם צָרִיךְ לִהְיוֹת בִּשְׁתֵּי בְּחִינוֹת וּמַדְרֵגוֹת,

namely, the category of a servant, who serves his master out of fear, and the category of a son, who serves his father out of love.

וְהֵן: בְּחִינַת "עֶבֶד" וּבְחִינַת "בֵּן".

And although one may find a son who is also a servant, it is impossible to attain to this degree without the prerequisite of the higher level of fear and awe known as yirah ilaah, as is known to the initiated.

וְאַף דְּיֵשׁ "בֵּן" שֶׁהוּא גַם כֵּן "עֶבֶד", הֲרֵי אִי אֶפְשָׁר לָבֹא לְמַדְרֵגָה זוֹ, בְּלִי קְדִימַת הַיִּרְאָה עִילָּאָה, כַּיָּדוּעַ לַיּוֹדְעִים:

It is clear from all the above that even if one loves G-d but lacks a fear of Him, his spiritual labors will not be of the kind that the Torah calls avodah, divine service. And should he fail in his attempts at awakening a fear of G-d in his heart, he should at least arouse a feeling of fear and awe in his mind.