Mark 12:30 And you shall love the Lord your God with all your innermost mind, and with all your vital force, and with all your reasoning mind, and with all your strength: this is the first commandment.
31 And the second corresponds, namely this, You shall love your neighbor as yourself. There is none other commandment greater than these.

Note that the most important command is to love the Lord.  This starts with reverence and holy awe toward Him. The sin against this commandment is the most serious sin.  From sins against this commandment, every other sin comes.  This is why Jesus said, the second corresponds, namely this, You shall love your neighbor as yourself." The second corresponds to the first because failure to follow the first causes the failure to follow the second. 

The Sin Romans 1:18 For the wrath of God is unveiled from heaven against all ungodliness and unrighteousness of men, who restrain the truth in poor judgment, * because that which may be known of God is plainly known among them, for God has made it visible it to them. Note  For the invisible things of Him from the creation of the world are clearly seen, being understood by the things that are made, even His eternal power and Godhead, so that they are without excuse, because, when they knew God, they didn't glorify Him as God, neither were they thankful, but they became vain in their imaginations, and their foolish innermost minds were darkened.

The Punishment Romans 1:24-32 Therefore God also gave them up into uncleanness through the desire for forbidden things that is within their own innermost minds, to dishonor their own bodies between themselves . . . 26 For this cause God gave them up to vile afflictions of the mind, for even their women changed the natural use into that which is against nature, And in the same way the men also, leaving the natural use of the woman, burned in their desire one toward another, men with men, committing indecent acts and receiving in themselves that penalty of their error that is just. And even as they did not like to retain God in their knowledge, God gave them over into their depraved minds to do those things which should never be done. * Being filled with all unrighteousness, fornication, wickedness, covetousness, desire to harm; full of envy, murder, debate, deceit, depravity; slanderers, Backbiters, haters of God, spiteful, proud, boasters, inventors of evil things, disobedient to parents, Without understanding, covenant breakers, without natural affection, implacable, unmerciful: Who knowing the judgment of God, that they which commit such things are worthy of death, not only do the same, but have pleasure in those who do them they know.

As you can see, all the other sins are the result of the first sin.  Honoring God is the beginning of wisdom.  Wisdom consists of righteousness, holiness, and being set free from sin's bondage.  And all of these sins must be judged by God--and the ungodly people (Atheists and all who do not acknowledge God) actually know that they will be judged.  But they are defiant.