【Impious】 , 【profane】 ,  【blasphemous】 ,  【sacrilegious】  mean showing marked irreverence for what is sacred or divine.

【Impious】 usually implies extreme disrespect for God or the laws of God or for those endowed with God-given authority particularly as shown positively in thought or in actions.

【Profane】  (see  【PROFANE】 1 ) applies to men and to words and acts that manifest not only impiety but defilement or desecration, sometimes thoughtless and sometimes intentional, of what is worthy of highest reverence or respect.

【Blasphemous】  (compare BLASPHEMY ) adds to  【profane】 the implication of indignity, either deliberate or inadvertent, offered directly or indirectly to the Supreme Being.

【Sacrilegious】  basically implies the commission of a sacrilege (see PROFANATION ), but in its more usual extended sense it implies the defilement of what is holy or sacred (as by acts of depredation, disrespect, or contempt.