Sin lies only in hurting other people unnecessarily. All other sins are invented nonsense. (Hurting yourself is not sinful--just stupid.)
One man's religion is another man's belly laugh.
The most ridiculous concept ever perpetrated by H.Sapiens is that the Lord God of Creation, Shaper and Ruler of the Universes, wants the sacharrine adoration of his creations, that he can be persuaded by their prayers, and becomes petulant if he does not recieve this flattery. Yet this ridiculous notion, without one real shred of evidence to bolster it, has gone on to found one of the oldest, largest and least productive industries in history.
23. It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so, and will follow it by suppressing opposition, subverting all education to seize early the minds of the young, and by killing, locking up, or driving underground all heretics. [Robert A. Heinlein, Postscript to Revolt in 2100]
24. But I contend that the disgusting behavior of many of their alleged 'holy men' relieves us of any intellectual obligation to take the stuff seriously. No amount of sanctimonious rationalization can make such behavior anything but pathological.
25. A religion is sometime a source of happiness, and I would not deprive anyone of happiness. But it is a comfort appropriate for the weak, not for the strong. The great trouble with religion - any religion - is that a religionist, having accepted certain propositions by faith, cannot thereafter judge those propositions by evidence. One may bask at the warm fire of faith or choose to live in the bleak certainty of reason- but one cannot have both. [Robert A. Heinlein, from "Friday"]