Jesus is our brother by virtue of His humanity, and He is our Father by virtue of His deity.
To paraphrase, Jesus became our brother in the days of His flesh – that is, from the time He was conceived in Mary’s womb by the Holy Spirit through His suffering and death. He was tempted in all points as we are, yet without sin (Hebrews 4:15). He became our Father in the days of His resurrection to, and glorification in, heaven. We were begotten from His seed (1 Peter 1:23), and we are thus His children and He is our heavenly Father.
For this reason Isaiah prophesied that the “Son” would be called “Father” (Isaiah 9:6), and that there would be no end to this arrangement (Isaiah 9:6-7). Thus we may rightly say that Jesus was our brother but is our Father (2 Corinthians 5:16) in the same way that He was David’s son but is David’s Lord (Matthew 22:41-46; Acts 2:34-36).
One of the problems with the Trinity doctrine is that it tries to keep Jesus as our brother and won’t let Him be our Father.
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