Heidelberg Catechism 16.44

Chapter 16 — Lord's Day 16

Section 44. Q. 44: Why does the creed add, 'He descended to hell'? A. To assure me during attacks of deepest dread and temptation that Christ my Lord, by suffering unspeakable anguish, pain, and terror of soul, on the cross but also earlier, has delivered me from hellish anguish and torment.