We know the doctrine of adoption is true because it is explicitly stated in Scripture, particularly in Romans 8:15, where believers are assured of their family status with God.
The truth of the doctrine of adoption is rooted in both the teachings of Scripture and the work of Christ. Romans 8:15 clearly states that believers have received the spirit of adoption, confirming their status as children of God. Furthermore, this doctrine is reflected in the life and work of Jesus Christ, who through His sacrificial death and resurrection makes it possible for sinners to be reconciled to God. The Holy Spirit also bears witness with our spirit that we are indeed children of God (Romans 8:16), providing believers with internal assurance of their salvation and familial relationship with God. Thus, the evidence lies in both Scripture and personal experience of faith.
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