Death, to a good man is but passing through a dark entry, out of one little dusky room of his Father’s house, into another that is fair and large, lightsome and glorious, and divinely entertaining.

Isaac Watts (1674–1748) English theologian and hymnodist

Miscellaneous Thoughts in Prose and Verse [Reliquiæ Juveniles], ch. 32 “Earth, Heaven, and Hell” (1734)
    (Source)

This phrase is often misattributed to Adam Clarke (1762-1832) (e.g., 1853, 1853, 1876, 1880, 1888) or Samuel Clarke (1727-1769) (e.g., 1827). Finding the primary source confirms Watts' authorship, though it is possible that others used the passage in sermons and writings, and the attribution was misremembered.