If you were to ask some random people what they feared, most would probably say bugs, heights, and closed spaces. You most likely will not hear someone say that they fear God. While it may seem that because God is so loving we should not fear Him, the Bible tells us otherwise.
Dictionary.com defines fear as an "extreme reverence or awe, as toward a supreme power". Just like a little kid who has done something wrong fears the punishment they are going to get from their parents, we as Christians should be fearful of our Heavenly Father. He is in control of everything and has ultimate power over it all. With such supreme majesty, why do we all continue to do wrong even though we know He doesn't like it?
Psalm 34:11 says, "Come, my children, listen to me; I will teach you the fear of the LORD." To fear God is not to be scared of Him in a way that you run from Him, but to have an "extreme reverence or awe" for Him and His ruling over us. It's one thing to know the rules that God has for us, it's another to actually do them.
When we do what we know is wrong, we are ultimately telling God that we do not respect His authority and rule over us. Constantly be aware of God's presence in everything and show Him the reverence and awe that He deserves. "Now [that] all has been heard, here is the conclusion of the matter: Fear God and keep his commandments, for this is the whole duty of man" (Ecclesiastes 12:13).