MRankens, think on these things. In the example of Matthew 12:36-37 The Messiah was speaking of words from the heart (idle words), but when people's words do not match their actions, then the actions speak louder.
Paul and Timothy or any Apostle, they all have the same mind as Messiah.
1 Corinthians 2:16 For who hath known the mind of the Lord, that he may instruct him? But we have the mind of Messiah (and he has the mind or Spirit of YHVH).
It is not wrong for the living to mourn the Messiah. When Scripture says let the dead bury the dead, it means let the Spiritually dead bury the Spiritually dead, and has no bearing on the Spiritually Living at all.
There is nothing wrong with recognizing birthdays, but I do not celebrate them. However, the deciding factor in any celebration is whether it was and is now being used to worship a pagan god in YHVH's righteous name. This is an unacceptable blending of unrighteousness with Righteousness.
Deuteronomy 12:30-31 (excerpt)
. . . . . . . enquire not after their (pagan) gods, saying, How did these nations serve their (pagan) gods? even so will I do likewise (unto YHVH).
31 Thou shalt not do so unto the LORD thy GOD: . . . . .
Blessings and not cursings