Ruth 4:17

"A son has been born to Naomi." Similar to "And she had a son."

"Father of David." It's possible that the lineage goes through both Oved and Yishai, akin to "God of my father Abraham and God of my father Isaac," reasoning that Nachshon died in the desert before Israel's entry, for he couldn't have been a youth leading the tribe while Israel journeyed initially. Moreover, the text mentions him entering the land, implying he'd be the tribe's leader. Hence, between his entering the land and David's birth, only six years passed, as it's written, "In the four hundred and eightieth year after the Israelites had come out of Egypt, in the fourth year of Solomon's reign." David lived for seventy years. Forty years the Israelites journeyed in the desert. If we say Salmon entered the land at one year old, then Salmon, Boaz, Oved, and Yishai each fathered a child at ninety-one years old. If we assume Nachshon was less than twenty when leaving Egypt, he'd be eighteen years old, accounting for the years in the desert. So, the sum would be five, and each would father a child at eighty-four. This seems plausible, as Boaz was already elderly, which Ruth knew, as he told her not to go after the young men. Yishai was also old when he fathered David, as he was the eighth son. Perhaps Oved was named because he was fathered by an elderly man, and the woman only accepted him for the sake of God's honor. Additionally, his mother left her religion and homeland, taking refuge under God's wings. Therefore, the child would be named Oved Hashem (a servant of God), as most children resemble their parents, as they are the roots.