Elisha'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).


Elisha's Explanation

When Elisha spoke about Lord Jesus Christ(Word of the Lord), The Bible says that our Lord reveled his Trinity in the battle field, so the Syrians heard three types of noises (noise of chariots, noise of horses, noise of a great host), and just by hearing the noise the whole Syrians army ran away for the life - 1.But Elisha said, “Hear the word of the Lord: thus says the Lord, Tomorrow about this time a seah of fine flour shall be sold for a shekel, and two seahs of barley for a shekel, at the gate of Samaria.” 2.Then the captain on whose hand the king leaned said to the man of God, “If the Lord himself should make windows in heaven, could this thing be?” But he said, “You shall see it with your own eyes, but you shall not eat of it.” 3.Now there were four men who were lepers[c] at the entrance to the gate. And they said to one another, “Why are we sitting here until we die? 4.If we say, ‘Let us enter the city,’ the famine is in the city, and we shall die there. And if we sit here, we die also. So now come, let us go over to the camp of the Syrians. If they spare our lives we shall live, and if they kill us we shall but die.” 5.So they arose at twilight to go to the camp of the Syrians. But when they came to the edge of the camp of the Syrians, behold, there was no one there. 6.For the Lord had made the host of the Syrians to hear a noise of chariots, and a noise of horses, even the noise of a great host: and they said one to another, Lo, the king of Israel hath hired against us the kings of the Hittites, and the kings of the Egyptians, to come upon us 7.So they fled away in the twilight and abandoned their tents, their horses, and their donkeys, leaving the camp as it was, and fled for their lives. 8.And when these lepers came to the edge of the camp, they went into a tent and ate and drank, and they carried off silver and gold and clothing and went and hid them. Then they came back and entered another tent and carried off things from it and went and hid them. 9.Then they said to one another, “We are not doing right. This day is a day of good news. If we are silent and wait until the morning light, punishment will overtake us. Now therefore come; let us go and tell the king's household - 2 Kings 7:1-9

When the Lord made the whole Syrian's army to hear the great noise which could terrify everyone of them and made them to run for the lift, the four lepers have not heard any sound and they were calmly walking towards the Syrian's army, that is the power of our Lord Jesus Christ.