Can we eat from the food of Christian thanksgiving?
Yes, you can eat from the food of Christian thanksgiving.
Allah the Almighty commands:
“This day, all good things have been made lawful to you. The food of those who are given the book is lawful for you and your food is lawful for them. The chaste women, be they either from among the believers or from among those who were given the book before you, provided you become their protectors in wedlock after paying them their bridal-due, rather than go around committing fornication and taking them as secret-companions. All works of those who refuse to follow the way of faith will go waste, and he will be among the utter losers in the hereafter.” (The Feast 5:5)