What is blasphemy? I will give you a definition; I will give you my thought upon this subject. What is real blasphemy?
To live on the unpaid labor of other men — that is blasphemy.
To enslave your fellow-man, to put chains upon his body — that is blasphemy.
To enslave the minds of men, to put manacles upon the brain, padlocks upon the lips — that is blasphemy.
To deny what you believe to be true, to admit to be true what you believe to be a lie — that is blasphemy.
To strike the weak and unprotected, in order that you may gain the applause of the ignorant and superstitious mob — that is blasphemy.
To persecute the intelligent few, at the command of the ignorant many — that is blasphemy.
To forge chains, to build dungeons, for your honest fellow-men — that is blasphemy.
To pollute the souls of children with the dogma of eternal pain — that is blasphemy.
To violate your conscience — that is blasphemy.
The jury that gives an unjust verdict, and the judge who pronounces an unjust sentence, are blasphemers.
The man who bows to public opinion against his better judgment and against his honest conviction, is a blasphemer.

Robert Green Ingersoll (1833-1899) American lawyer, agnostic, orator

Trial of C.B. Reynolds for blasphemy (May 1887)
    (Source)