John Gill Commentary Judges 18:19

"And they said unto him, Hold thy peace, lay thy hand upon thy mouth, and go with us, and be to us a father and a priest: is it better for thee to be priest unto the house of one man, or to be priest unto a tribe and a family in Israel?" — Judges 18:19 (ASV)

And they said to him, hold your peace
Be silent, make no disturbance, be quiet and easy:

lay your hand upon your mouth ;
as a token of silence; so the Egyptians used to paint Harpocrates, the god of silence, with his fingers pressing his lips:

and go with us ;
for they wanted him as well as his gods, not knowing well how to make use of them without him:

and be to us a father and a priest ;
to direct them, instruct them, perform acts of devotion for them, and ask counsel on their account; it seems as if it was common in those days to call a priest a father, see (Judges 17:10)

is it better for you to be a priest to the house of one man, or that
you be a priest to a tribe and a family in Israel ?
suggesting, that it must be much more honourable for him, and more to his advantage, to officiate as a priest to a body of people, that might be called a tribe, or to a family consisting of various houses, than in the house of a private person; this they left him to consider and judge of.