Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) said: "Let none of you belittle himself, in that there is a command of Allah concerning which there is something for him to say, and he does not do it. He will meet Allah, and Allah Almighty will say: 'Why did you not do such-and-such on such-and-such a day?' He will say: 'O Allah, I feared the people.' Then Allah Almighty will say: 'It was more fitting that you should fear Me.'"
Hadith Referenceالسنن الكبرى للبيهقي / كتاب آداب القاضي / 20184