Rebecca has a wonderful tradition of highlighting hymns on Sundays. I came across this one in a public domain hymnbook from Google, searching for "prophet, priest, and king." No idea what the tune is, but it can be sung to O For A Thousand Tongues...
Loved the words, so I thought I'd post it here.
Ye are complete in Him
I've found the pearl of greatest price;
My heart doth sing for joy;
And sing I must for Christ is mine--
Christ shall my song employ.
Christ is my Prophet, Priest, and King:
My Prophet full of light;
My great High Priest before the throne;
My King of heavenly might.
For he indeed is Lord of lords,
And he the King of kings;
He is the Sun of Righteousness,
With healing in his wings.
Christ is my Peace: he died for me,
For me he gave his blood;
And, as my wondrous sacrifice,
Offered himself to God.
Christ Jesus is my All in All,
My comfort and my love;
My life below, and he shall be
My joy and crown above.