What does the Bible say about eternal vital union?

Eternal vital union is a fundamental concept in Reformed theology, reflecting the intimate and real relationship between Christ and His elect. This union is established in Scripture, emphasizing that believers were chosen in Christ before the foundation of the world (Ephesians 1:4). Just as Adam's progeny are born from his physical lineage, believers are spiritually derived from Christ, the second Adam, whose life and blessings flow to us through this vital union. This connection means that Christ's nature and eternal life are present in His people, ensuring that we have a living relationship with Him, which is both real and eternal.