Say I leave to go to the store and I leave my daughter at home by herself. I want her to obey my rule of staying in the yard while I am gone, so while I am gone I tie her to a tree in the backyard to make sure she does not go anywhere. When I get home I ask my neighbor if she has been obedient. He says she's been right in the yard.
Now this shows neither obedience nor love. IF on the other hand I leave her in the back yard of her own freedom. Upon returning ask my neighbor the same question. He states she has not left the yard, even when the neighborhood troublemaker came by and tried to get her to leave. This shows true obedience and love.
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As for this comment...
So according to the student all atheists are evil since they don't have the love of God in their hearts? I know that I lead a life that is has far less evil in it than many of the "Christians" that I know. The professor's argument isn't the only one that is flawed here.
If you had a child that was a murderer would you want people using that in their opinion of you? A child of God (one who has been born again through faith by Jesus Christ), is not perfect, just forgiven.
Here is how it works. Most people think sin is black, the Bible says "Though your sins be as scarlet". So sin is red. Take a red marker and write a word on a sheet of paper. Now take the red side of some 3d glasses and look at the red writting. It appears white. So through Jesus (his blood shed for my sin that covers and pays my sin debt) let me finish the Biblical quote. Though your sins be as scarlet, they shall be made white as snow.
I, in my imperfections, cannot have a relationship with a righteous God, Jesus is the filter that allows Him to see me redeemed and made righteous. Not by anything I have done or could do. But by the sacrifice of His son Jesus.
Am I "more evil" or less "good" than some Athiest. Probably. Not the point. The "ruler" or measuring stick is Christ and he did not sin. Don't judge my God by my behavior. Be thankful that He is merciful, I don't think sometimes I could put up with me if I were God. I thank God I am forgiven, not free to sin, but free from the penalty.