As Christians we understand that God is three in one. This is the mystery of the Trinity that has been confessed by the Church since the earliest of Creeds.
In this mystery, we see that God is Father, Son and Holy Spirit—in perfect union and harmony. Our kingdom culture of family is derived from this very mystery.
When God created humanity, He created a family: a husband and wife. When God decided to choose a people to be HIS people, He chose a family (Abram and Sarai along with extended family). When Jesus was incarnated in human flesh, He was born into a family.
Likewise, when we choose to follow Jesus, we are adopted into a new family through a new covenant with Christ.
In this new family, we have a heavenly Father! Jesus Himself came to reveal the Father so that we might know Him. The Holy Spirit is the Spirit of adoption, who seals our heavenly adoption into this new family. The Trinity is a family affair into which we are invited!
Jesus told His disciples that those who do the will of God are His brothers and sisters. So, as the Body of Christ we have brothers and sisters in Christ who have become our family.
It is essential, therefore, that we honor one another as brothers and sisters. We honor those who are mothers and fathers in the faith, people who model what it looks like to be a son or daughter of God.