The Trinity is easily understood through marriage.
Mark 10:7 – “‘Therefore a man shall leave his father and mother and hold fast to his wife, 8 and the two shall become one flesh.’ So they are no longer two but one flesh.”
In a marriage covenant, two people become one.
John 10:30 – “I and the Father are one.”
Jesus is simply stating that He and His Father have the same nature and are in a covenant relationship.
Mark 12:29 – Jesus answered, “The most important is, ‘Hear, O Israel: The Lord our God, the Lord is one.'”
In the same way that metals can be fused or “married” together, the Lord our God, The Lord is married.
In a marriage relationship, the two people spend so much time around each other that the longer they are married the more they become alike in thought, word, emotion, deed, and all the other unnamed aspects. And so it that the Father, Son and Holy Spirit have been in relationship forever.
– 3 in 1 –
Let’s take a look at Jesus to better understand this:
Colossians 2:9 – For in Christ all the fullness of the Deity lives in bodily form.
Jesus is the Container of the Trinity; for in Him is the contents, character, and attributes of the Father and the Holy Spirit, because He’s been around Them. Jesus is our Triple Portion as well; for whoever receives Him receives the Father and the Spirit, because inside of the Man Jesus is the same exact nature of the Father and the Spirit.