Muslims are allowed to eat the meat offered by Jews and Christians. Muslims are also allowed to eat the meat offered by other Non-Muslims as long as the animal is not slaughtered in a name of something other than that of Allah.
Allah the Almighty commands:
“Say: I cannot find in what has been revealed to me anything forbidden for anyone who wants to eat unless it is carrion, outpoured blood and the swine flesh, all of which is unclean; or that which is slaughtered in a name other than that of Allah as a deliberate sin. (…)” (6/145, see also: 5/3)
“Allah has only forbidden you to eat what dies of itself, and blood and swine flesh and what has been consecrated to any other name than of Allah. (…)” (6/115, 2/173)
Some folks came to the Messenger of God and said: “Messenger of God! Some people bring us meat. We don’t know if they mentioned the name of Allah (while slaughtering them) or not. Can we eat them?” The Messenger of God replied: “Eat them by mentioning the name of Allah.” (Bukhari, Tawhid, 13, Sayd, 21; Abu Dawud, Adahi, 13-19; Nasai, Dahaya, 21; Ibn Majah, Zabaih, 4; Muwatta, Zabaih, 1)