Asaph's Explanation
Apostle John who was with Christ until his last moment of the crucifixion, has revealed that Jesus Christ is not the image of Word alone, but the Image of Father, Word and the Holy Spirit, and we must believe in him to overcome this world - 5.Who is it that overcomes the world? Only the one who believes that Jesus is the Son of God. 6.This is the one who came by water and blood—Jesus Christ. He did not come by water only, but by water and blood. And it is the Spirit who testifies, because the Spirit is the truth - 1 John 5:5-6
To understand this in a better way, apostle John first explaining the Trinity of our Heavenly Father as Father, Word and Holy Spirit - because there are three who are testifying in Heaven: the Father, the Word, and the Holy Spirit, and these three are one - 1 John 5:7
And then he explained about the Son Jesus Christ, that Jesus had all three of them(Father, Son, and the Holy Spirit) in him - and there are three who are testifying in the earth: the Spirit(Holy Spirit), and the water(Word), and the blood(Father) and the three are into the one(Jesus Christ) - 1 John 5:8
That was the reason Apostle Paul is saying that Jesus Christ is the Image of the invisible God - The Son is the image of the invisible God, the firstborn over all creation - Colossians 1:15 that means in Jesus Christ we can see the Son (The Word became flesh - John 1:14), and our Heavenly Father (Father is in me - John 10:38), and the Holy Spirit (Spirit of the Lord is upon me - Luke 4:18).
Asaph's Explanation
Jesus Christ the first one who called the Heavenly God as My Father, when he called God as My Father, Jesus reveled the Truth that He is the Son of God, but the Jewish could not accept Christ as a Son of God tried to stone him - 22.At that time the Feast of Dedication took place at Jerusalem. It was winter, 23.and Jesus was walking in the temple, in the colonnade of Solomon. 24.So the Jews gathered around him and said to him, “How long will you keep us in suspense? If you are the Christ, tell us plainly.” 25.Jesus answered them, “I told you, and you do not believe. The works that I do in my Father's name bear witness about me, 26.but you do not believe because you are not among my sheep. 27.My sheep hear my voice, and I know them, and they follow me. 28.I give them eternal life, and they will never perish, and no one will snatch them out of my hand. 29.My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father's hand. 30.I and the Father are one.” 31.The Jews picked up stones again to stone him. 32.Jesus answered them, I have shown you many good works from the Father; for which of them are you going to stone me? 33.The Jews answered him, It is not for a good work that we are going to stone you but for blasphemy, because you, being a man, make yourself God - John 10:22-33
When Jewish tried to stone the Son of God Jesus Christ, he referred the revelation of prophet Asaph written in the Book of Psalms - 34.Jesus answered them, Is it not written in your Law, I said, you are gods. 35.If he called them gods to whom the word of God came—and Scripture cannot be broken— 36.do you say of him whom the Father consecrated and sent into the world, ‘You are blaspheming,’ because I said, I am the Son of God? 37.If I am not doing the works of my Father, then do not believe me; 38.but if I do them, even though you do not believe me, believe the works, that you may know and understand that the Father is in me and I am in the Father.” - John 10:32-38
Actually, the prophet Asaph's revelation talks about Jesus Christ and also about his Trinity(Father, Word, and the Holy Spirit) - I said, You are Gods, Sons of the Most High, all of you; nevertheless, like men you shall die, and fall like any prince. Arise, O God, judge the earth; for you shall inherit all the nations - Psalm 82:6-8
In this revelation, we can see Trinity God calling the Son Jesus Christ in Plural manner, because the Word, Father and the Holy Spirit all three of them were dwelling in Jesus Christ - I said, You are Gods, Sons of the Most High, all of you - Psalm 82:6
Though the Son Jesus Christ has Trinity with in himself, This prophecy tells that the they all have to taste the death as a single man for our sin and salvation - But you shall die like men, And fall like one of the princes - Psalm 82:7
And finally this revelation also tells that death can not hold our Lord Jesus Christ, and he will raise from the death and rule the whole world - Arise, O God, judge the earth; for you shall inherit all the nations - Psalm 82:8