The Ramchal identifies two levels of yirah: yirat hachet (fear of sin and its consequences) and yirat haRomemus (awe of God's exalted greatness). He describes yirat haRomemus as the higher and more complete form of yirah, and outlines the contemplative and behavioral practices that lead to it.
אָמְנָם צָרִיךְ שֶׁנַּקְדִּים כִּי מִינֵי הַיִּרְאָה הֵם שְׁנַיִם שֶׁהֵם שְׁלֹשָׁה: הָרִאשׁוֹנָה קַלָּה מְאֹד לְהַשִּׂיגָהּ אֵין דָּבָר קַל כָּמוֹהוּ, וְהַשְּׁנִיָּה קָשָׁה מִן הַכֹּל. וּשְׁלֵמוּתָהּ כְּמוֹ כֵן שְׁלֵמוּת גָּדוֹל מְאֹד. יֵשׁ יִרְאַת הָעֹנֶשׁ, וְזֶהוּ הַמִּין הָאֶחָד, וְיֵשׁ יִרְאַת הָרוֹמְמוּת, וְזֶהוּ הַמִּין הַשֵּׁנִי, שֶׁיִּרְאַת הַחֵטְא חֵלֶק שֵׁנִי מִמֶּנּוּ, וּנְבָאֵר עַתָּה עִנְיָנָם וְהֶבְדְּלֵיהֶם. הַמִּין הַשֵּׁנִי הוּא יִרְאַת הָרוֹמְמוּת, וְהוּא שֶׁהָאָדָם יִרְחַק מִן הַחֲטָאִים, וְלֹא יַעֲשֶׂה מִפְּנֵי כְּבוֹדוֹ הַגָּדוֹל יִתְבָּרַךְ שְׁמוֹ, כִּי אֵיךְ יֵחָל, אוֹ אֵיךְ יֶעֱרַב לִבּוֹ שֶׁל בָּשָׂר וָדָם שָׁפֵל וְנִמְאָס לַעֲשׂוֹת דָּבָר נֶגֶד רְצוֹנוֹ שֶׁל הַבּוֹרֵא יִתְבָּרַךְ וְיִתְעַלֶּה שְׁמוֹ? וְהִנֵּה זֹאת הַיִּרְאָה אֵינָהּ כָּל כָּךְ קַלָּה לְהַשִּׂיג אוֹתָהּ, כִּי לֹא תִּוָּלֵד אֶלָּא מִתּוֹךְ יְדִיעָה וְהַשְׂכָּלָה לְהִתְבּוֹנֵן עַל רוֹמְמוּתוֹ יִתְבָּרַךְ, וְעַל פְּחִיתוּתוֹ שֶׁל הָאָדָם, כָּל אֵלֶּה דְּבָרִים מִתּוֹלְדוֹת הַשֵּׂכֶל הַמֵּבִין וּמַשְׂכִּיל. וְהִיא הַיִּרְאָה אֲשֶׁר שַׂמְנוּהָ לְחֵלֶק שֵׁנִי מֵאֶחָד מֵחֶלְקֵי הַחֲסִידוּת אֲשֶׁר זָכַרְנוּ.
However, we must first introduce that there are two types of fear which are effectively three types. The first type is very easy to attain, there being nothing easier. The second is difficult, while the second part of the second type, is more difficult than everything. Its perfection is likewise, a very great form of perfection. The first type is fear of punishment, and the second is fear of G-d's exaltedness (Yirat Haromemut), of which Fear of Sin is the second part therein. We will now explain their matters and differences. The second type of fear is fear of G-d's exaltedness (Yirat Haromemut). It means that a person distances and refrains from sin because of G-d's great honor, blessed be His Name. For how could his heart of flesh and blood, lowly and petty, allow or dare do something against the will of the Creator, blessed and exalted be His Name?! This type of fear is not so easy to attain, for it will arise only out of knowledge and thought, [namely] by contemplating G-d's exaltedness, blessed be He, and the lowliness of man. All these things are outgrowths of the intellect which understands and attains insight. This is the fear we described previously in Piety, setting it as the second part of one of the divisions of Piety.