Character stays the same. You have a confusion as to what staying the same means.Jesus remains the same forever. It's people who change.
Mal 3:6: "For I am the LORD, I change not; therefore ye sons of Jacob are not consumed."
See, it's about His character of mercy, justice and love.
The Son of God in heaven before taking upon Himself the likeness of sinful flesh did not eat animal flesh, for there is no death in heaven.
He also moved from the Most Holy place in Heaven down here to the courtyard of earth and took upon Himself the likeness of sinful flesh.
He lived and died.
He resurrected and ascended
He is back in Heaven where there is no more eating of flesh. He is now once again in the Most Holy place where no dead flesh comes.
We are to follow Him (the lamb) wheresoever He goes. Are you with Him in Heaven, in the Most Holy place by faith, or are you stuck in the past with your mind upon earthly things (like eating flesh)?
Even in the natural world here, when people prepare to go to a foreign land, another country, they begin to practice the language of that place, might begin to wear the clothing of that place, practice some of the customs of that place, and even eat the diet/food of that place, to make for a smooth transition from your old location to the new.
Natural to spiritual (1 Cor. 15:46).