Is it permitted say any of the following to a Christian colleague:
1) Merry Christmas
2) Happy Xmas
3) Happy Holidays
I am specifically referring to initiating a greeting not responding to such a greeting as mentioned elsewhere December greeting responses or when giving a gift.
Also would there be a difference between let's say seeing someone and wishing them "Merry .." or using the phrase when thanking someone for a service (like saying it to a cashier) ?
Is writing it in a email different than saying it ?