135. Are we permitted to eat meat of animals sacrificed at Altars?

The verses (5:3, 5:90, 70:43) of the Quran say those animals sacrificed at altars are not to be eaten by Muslims . These verses were revealed, referring to the earlier days practice of slaughtering animals by placing them upright in the altars by Arabs. 

We need to understand these verses to mean the altar as a bed of stones with butcher blocks and anointed things at the shrine or mausoleum of dead people.

There is a number of evidence in various Hadiths regarding this.

Refer explanation point 427 for more details