A very important exercise to practice to attain the fear of the Lord is this: do not do in secret what you are ashamed to do before people. Do not have any thought which you cannot reveal before people. Say to yourself, “I should be ashamed from God who sees me and examines my thoughts, my intentions and the desires of my heart. 

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Try, then, to be righteous before yourself as much as you are before others. Avoid any speculation which would make you embarrassed if others knew it, likewise with your deeds and emotions.

Fear of God
H.H. Pope Shenouda III