Hebrews 10:31

10:31 It is a terrifying thing to fall into the hands of the living God.

Hebrews 12:22

12:22 But you have come to Mount Zion, the city ¹  of the living God, the heavenly Jerusalem, and to myriads of angels, to the assembly

[12:22]  ¹ tn Grk “and the city”; the conjunction is omitted in translation since it seems to be functioning epexegetically – that is, explaining further what is meant by “Mount Zion.”