The Holy Spirit confirms our adoption into God's family through faith in Jesus Christ, that we may know Him as our Father. Jesus taught us to address God as our Father in prayer. Through faith in Christ, the Holy Spirit brings us to know God as our Father. We come to God as our Father in Christ by the Holy Spirit.
"For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, 'Abba! Father!' The Spirit himself bears witness with our spirit that we are children of God" (Romans 8:15-16, ESV).
In New Testament days, the Roman law for adoption illustrated how we are adopted into God's family to know Him as our Father. In those days, if an older man did not have a son, he could adopt one according to the law. First, he must choose the son. Second, he must pay a price to adopt a son. Third, there must be witnesses present at the official adoption ceremony.
The illustration makes it clear how we are adopted to know God as our Father. God chose us in Christ (Ephesians 1:4-6). He paid the price through His only begotten Son at the cross. Jesus paid it all for us to be God's adopted children. The Holy Spirit is the witness that we are adopted as God's children by faith in our Lord Jesus Christ.
