This Thursday my family is having a gathering with the intention to make my grandmother happy ( e.g. so that she can be with her family). But, the intention is also because it is Thanksgiving. There will be turkey and the likes. Some of my family is not Muslim by the way. But, am I allowed to go even though it may be slightly with the intention of Thanksgiving? Could you provide evidence from Quran and Hadith please. Thank you very much.
In the name of Allah, the Ever-Merciful
Walaykum salam rahmatullahi barakutu.
Celebrating Thanksgivings is not allowed and it is considered bidat or innovation. The dalil is:
The Prophet Muhammad (S.A.W.) said, "Whoever imitates some people, he is considered as one of them." In another narration the prophet (S.A.W.) said, "A person is not one of us (Muslims), if he imitates others (non-Muslims). (Reported by Imam Ahmad).
"Whoever resembles a people is one of them." (Recorded by Abu Dawood)
Also, when the Prophet (salallahu 'alayhi wasallam) arrived in Medinah he inquired of them, which were the days of celebrations. The Arabs used to celebrate the Persian New Year (Norus) and other days. The Prophet forbade them and said Allah has done away with all days of celebration and given us just two days of Eids.
Following the ways of the disbelievers - as opposed to the ways of the believers - and trying to come close to them is actually one of the characteristics of the hypocrites. Allâh says:"Give to the hypocrites the tidings that there is for them a painful torment. Those who take disbelievers for protectors and helpers instead of believers. Do they seek honor with them? Verily, all honor is with Allâh (alone)" (an-Nisaa, 138-139).
Unless, you will be going with the intention of giving D'awah to your family members and to teach them about Islam.
Allah knows best.