How do I solve 3 down in Times Cryptic 29531?

Question

Accepted Answer

3 down reads "Unusual Vermeer: thorned head dedicated to Christ" (8,6 letters); the answer is REVERENDMOTHER. It's an anagram clue: the answer is a rearrangement of letters supplied by the clue itself. Look for an indicator like 'mixed', 'broken', 'cooked', or 'wild', and find a phrase whose letters add up to the answer's length. The full step-by-step breakdown is on this page.

Unusual Vermeer: thorned head dedicated to Christ (8,6)

3D — Unusual Vermeer: thorned head dedicated to Christ (8,6) — REVERENDMOTHER