The most blasphemous thing a person can do is live a lie.
God loves people and created people for a relationship with Himself. Of course, people like to reject Him by embracing lies they make up in their own mind about Him.
Sometimes they even find groups of people that are willing to confirm their lies about Him.
They end up painting a picture of God in their own minds that make him look like the devil then they refuse to correct their mental pictures when the deficiencies in their mental picture is pointed out.
They all the time deliberately forget omniscience is a factor in God's life and death decisions.
Atheists can't know what God can know but that doesn't stop them from objecting to His decisions....anything to avoid granting control to God but control is an illusion for all human beings...
The only one that can be in control is God.
http://en.wikipedia.org/wiki/Illusion_of_control