Reference for Pirkei Avot 4:4
רַבִּי לְוִיטָס אִישׁ יַבְנֶה אוֹמֵר, מְאֹד מְאֹד הֱוֵי שְׁפַל רוּחַ, שֶׁתִּקְוַת אֱנוֹשׁ רִמָּה. רַבִּי יוֹחָנָן בֶּן בְּרוֹקָא אוֹמֵר, כָּל הַמְחַלֵּל שֵׁם שָׁמַיִם בַּסֵּתֶר, נִפְרָעִין מִמֶּנּוּ בְגָלוּי. אֶחָד שׁוֹגֵג וְאֶחָד מֵזִיד בְּחִלּוּל הַשֵּׁם:
R. Levitas Ish Yavneh says: Be extremely lowly spirited, for the "hope" of man is worms. [Even though in the other middoth the middle course is the best, with "pride," it is not so, but one must incline to the extreme of lowliness of spirit. For pride is especially despised. And, what is more, most men go astray in it, so that people are not disposed to separate from it, wherefore it requires especial distancing.] R. Yochanan ben Broka says: If one desecrates the name of Heaven in secret, it is exacted of him in the open. Both the unwitting and the witting are liable for desecration of the Name.