The answer is: King David

Matt 1:1 - It was important to trace the genealogy of Jesus back to David as the promise had been made that the Messiah would be part of his family (Jer 23:5)

The lineage of Jesus, specifically his descent from King David, serves as a vital link to the messianic prophecies found throughout scripture. King David, the iconic ruler who united Israel and established Jerusalem as its capital, was more than just a historical figure; he symbolized the hope for a future king who would usher in peace and righteousness. This is why descendants through Davidic lineage matter—they resonate with ancient expectations recorded through the prophets and laid the groundwork for Jesus' divine mission.

Interestingly, the genealogy in Matthew opens with words similar to the Jewish tradition. It starts with "the book of the lineage," which evokes thoughts of important history and identity. But here’s a quirky twist—Jesus's family tree isn’t flawless! Matthew includes names like Tamar and Rahab—non-Israelites with stories packed with surprises and scandal. This hints at a much broader understanding of acceptance and redemption than was traditionally nurtured.

Throughout the New Testament, the profound messages of love and inclusion take center stage, reflecting how Jesus’ mission transcended lineage. Such themes resonate with Old Testament echoes, where God often promised to fulfill His plans in unpredictable ways—using the unexpected for His wonders, like Samuel anointing David over his older brothers. Overall, tracing Jesus back to David isn’t just about royalty, but a rich tapestry of failed expectations, divine grace, and a path towards unity for all people.