Lay thy hand upon thy mouth, i.e. be silent, as this phrase is used, Job 21:5, Job 29:9 40:4 Proverbs 30:32. The same thing repeated in other words. A father and a priest: See Poole on "Judges 17:10". A family in Israel, to wit, a tribe that is (and being oft put for that is) a family. For it is certain this was not an expedition of the whole tribe, which numbered 64,000 men, Numbers 26:43, but only of one family, which it seems were more vexed with the Philistines or Amorites, and therefore resolved to seek new habitations at a great distance from them. And after this time we find the body of the Danites in their old and proper portions in Samson's time, which, though placed before this, was long after it.
Related Commentaries of Judges 18:19
Judges 18:19
19 And they said unto him, Hold thy peace, lay thine hand upon thy mouth, and go with us, and be to us a father and a priest: is it better for thee to be a priest unto the house of one man, or that thou be a priest unto a tribe and a family in Israel?