Answer:
I am a box that holds keys without locks, yet they can unlock your soul.
What is never used unless it's in a tight place?
My first is in fish but no in snail. My second is in rabbit but no in tail. My third is in up but not in down. My fourth is in tiara but not in crown. My fifth is in tree you plainly see. My whole a food for you and me.
When there is fire in me then I am still cold. When I own your true love’s face then you will not see me. To all things I give no more than I am given. In time I may have all things, and yet I can keep nothing.
What starts with a 'T', ends with a 'T', and has T in it?
An open ended barrel, it is shaped like a hive. It is filled with the flesh, and the flesh is alive!