Romans 14:5-6

5In the same way, some think one day is more holy than another day, while others think every day is alike. You should each be fully convinced that whichever day you choose is acceptable.

6Those who worship the Lord on a special day do it to honor him. Those who eat any kind of food do so to honor the Lord, since they give thanks to God before eating. And those who refuse to eat certain foods also want to please the Lord and give thanks to God.