What does Hrothgar promise Beowulf if he successfully kills Grendel - quote the line

Hrothgar wishes Beowulf luck and promises him anything he might ask for if he can defeat Grendel.

“Never to any man erst I trusted,

since I could heave up hand and shield,

this noble Dane-Hall, till now to thee.  

Have now and hold this house unpeered;  

remember thy glory; thy might declare;   watch for the foe!

No wish shall fail thee   if thou bidest the battle with bold-won life.”