Priest Dominic is trying to obtain something hidden in the Monastery of Silence. He will reward you if you can bring the Monk Scriptures to him.
In addition, he asks you to help Gremory if you meet him in the Monestary.

Monsters to Hunt: All the monsters in the Monestary of Silence

Gremory has snuck into the Monastery of Silence and is looking for the Grail of Splendor. He asks you to examine the Grail in the Room of Splendor.

You have finished looking over the Grail in the Room of Splendor as Gremory asked. Return to Gremory.

Since you examined the Grail for him, Gremory will exchange 4000 Monk's Scriptures for an Enchant Weapon Scroll (S-Grade) and 400 Monk's Scriptures for an Enchant Armor Scroll (S-Grade ).
Therefore, you can be rewarded by both Dominic and Gremory if you collect the Monk Scriptures.

Monsters to Hunt: All the monsters in the Monastery of Silence