The Lord, the Slave, the Peasant, and the King
Unlike in life, in death the self-same thing.

[Mors dominos servis et sceptra ligonibus æquat,
Dissimiles simili conditione trahens.]

Walter Colman
Walter Colman (1600-1645) English Franciscan friar
“La Danse Machabre or Death’s Duell,” st. 262 (c. 1633)
    (Source)

In Hoyt's New Cyclopedia of Practical Quotations (1922), this is translated:

Death levels master and slave, the sceptre and the law,
and makes the unlike like.