Adam Clarke on Ruth 4:17

The neighbors gave it a name - That is, they recommended a name suitable to the circumstances of the case; and the parents and grandmother adopted it.

They called his name Obed - עובד obed, serving, from עבד abad, he served. Why was this name given? Because he was to be the nourisher of her old age, Rut 4:15. And so he must be by lying in her bosom, even if services in future life were wholly left out of the question. These neighbors of Naomi were skillful people. See on Rut 4:16 (note). Other meanings, of which I am not ignorant, have been derived from these words; those who prefer them have my consent.

He is the father of Jesse, the father of David - And for the sake of this conclusion, to ascertain the line of David, and in the counsel of God to fix and ascertain the line of the Messiah was this instructive little book written.