Perception of God Determined by Perception of Sin

And the Lord passed by before him, and proclaimed, The Lord, The Lord God, merciful and gracious, longsuffering, and abundant in goodness and truth, keeping mercy for thousands, forgiving iniquity and transgression and sin, and that will by no means clear the guilty; visiting the iniquity of the fathers upon the children, and upon the children's children, unto the third and to the fourth generation. (Exodus 34:6-7 KJV)

God, in His proclamation to Moses, declared Himself to be merciful and gracious. However, many atheists and unbelievers have a very different opinion of Him.

Richard Dawkins, in his book "The God Delusion", wrote of God as follows:
QUOTE
The God of the Old Testament is arguably the most unpleasant character of all fiction: jealous and proud of it; a petty, unjust, unforgiving control-freak; a vindictive, bloodthirsty ethnic cleanser; a misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously malevolent bully.
UNQUOTE

An article in the huffingtonpost.com, "The Embarrassment of Noah" by Ronald A. Lindsay, described God as a moral monster.
QUOTE
Let's not mince words: if the story of the Flood is to be believed, God is a moral monster. To say his response to the alleged wickedness of humans is disproportionate is a gross understatement. Moreover, God engages in conduct that we would expect from the worst dictators, namely collective punishment that sweeps in the innocent along with the guilty. Children, presumably, were among those drowned (unless we assume that wicked adults had no offspring) as were most all of the animals, who bore no responsibility whatsoever for the misdeeds of humans. Intentionally drowning a kitten is conduct we'd expect of some psychopathic juvenile, not a loving deity.
UNQUOTE

Jim Holt gave his view on God in this tweet:
"I think God is 100% benevolent but only 80% effective," - Jim Holt
(Tweets by Barnyardstories@BrianJBarnes442 11:11 AM - 2 Sep 2014)

Why such big discrepancy in God's own view of Himself and the views of atheists and unbelievers of Him? The main reason is the perception of sin. God views Himself as extremely merciful despite the hatefulness of sin committed by men. The atheists and unbelievers have very low view of sin, believing that most sins are okay and can be ignored.