In Col 2:17 we read, "which are a shadow of things to come, but the substance is of Christ."
This verse is talking about the Old Testament things that are a 'shadow' but the 'substance' or real thing that is shadowed is of Jesus Christ.
We understand that if we see a shadow of a tree -- the substance (or reality) of the tree casting the shadow is nearby. The tree is the 'real' thing and the 'shadow' something that points to or indicates that there is a tree.
Therefore to understand how the gospel is preached to or through Abraham we have to see the Old Testament story pieces as the 'shadow' of the 'good thing' it shadows.
There are two important keys to keep in mind that unlock the mysteries of understanding how the things of the Old Testament point to the things of Jesus and the New Covenant.
ONE - The 'shadow' that we see in the Old Testament is 'physical' or real in earthly terms, but the 'substance' is real in the eternal spiritual sense. Because the 'shadow' is physical in earthly terms, the shadow is oft more real to us than the real thing which being spiritual, is invisible to us.
TWO - A physical aspect of a shadow picture must point to a spiritual reality.
An earthly physical shadow piece will never point to another physical piece. It must always correspond to the spiritual reality it is pointing to.
This is also called 'types and antitypes'. The type being the shadow or the thing that points and the antitype is the spiritual reality being pointed to. (see Rom. 5:14 and I Peter 3:21 for use of these terms - though some translations have used other words such as symbolize instead of type or anti-type)
So lets see if we can follow the pointing fingers of our Abraham/Melchezidek story and uncover a portrayal of the gospel story that would not yet be seen for thousands of years in the future.
The shadow pieces we are given are....
1. Melchizedek -- we are given strong hints in the NT about him -- Melchizedek was King of Salem and the High Priest of God - an usual duel role -- no one else except Jesus was both King and High Priest. Another unique detail is that Melchizedek was not a priest from the tribe of Levi, from which all all the priests of the covenant of Moses were taken. Neither was Jesus a High Priest from the tribe of Levi - hence we are told Jesus was a High Priest of the order of Melchizedek. So... we have strong indication that Melchizedek is pointing to Jesus.
2. Bread and Wine -- Here we are given more evidence to see Melchizedek as a shadow of Jesus. Melchizedek brought bread and wine to his meeting with Abraham. We know the bread and wine of the Old Testament Passover was revealed by Jesus Himself to be symbolic of His death - the sacrifice of his flesh - broken for us and His blood, poured out as the offering to cover our sin bringing salvation to all who would believe on Him.
3. Abraham -- we know Abraham is the father of all who live by faith -- so Abraham points to all those who have put their faith in the sacrifice of Jesus .. and then receiving His blessing of salvation.
4. Sodom and Gomorrah -- Sodom and Gomorrah have always, even until today, been synonymous with sin and worldliness so it is not a stretch to see that these cities point to the world lying in sin and wickedness. (II Peter 2:6)
5. The four Kings -- The four kings point to the enemy who seeks to overcome - to take captive at his will.
We see here our spiritual enemy pointed to, the prince of this world who takes souls captive at his will to keep them for himself under his control.
(I Tim 2:26)
6. Kings of Sodom and Gomorrah -- These kings represent the mirage of all this world can offer - power, riches, fame, self-gratification. Yet, at the first sign of trouble the "arm of flesh" or the security of this world will desert us, disappointing our trust in it. The world cannot save us, it will leave us defenceless and vulnerable to the enemy.
7. The Tenth of the plunder that Abraham offered to Melchizadek -- I have heard some suggest that is was the first example of paying the tithe and we are to follow Abraham's example , but that violates our rules of interpretation.
First - something physical in the Old Testament shadow cannot point to something physical in the New Covenant corresponding piece.. The pointing piece is physical , the piece pointed to must be spiritual. Therefore the physical tithe in the Old Testament shadow cannot be the tithe in the spiritual real thing.
Secondly - An important detail to note is that Abraham did not give a tenth of his own wealth or of his own possessions. He offered something that did not belong to him.
So what then could this 'tithe' point to as its spiritual corresponding piece ?
What can we 'give' to the Lord that comes out of the world, yet does not belong to us ?
Is it not the souls we win for Jesus ? God says all the souls belong to Him (Ez 18:4) so when we 'rescue' someone from out of the world and bring them to the Lord .. we bring to Jesus what never belonged to us. (I Cor. 9:22)
In looking at these story pieces we can see that the shadow story pieces point to Jesus and the gospel message.
God established His eternal covenant with Abraham promising that through Him all the world would be blessed. . (Gen. 12:3)
How is all the world blessed through Abraham ?
Abraham as the father of faith is pointing to his SEED , Jesus , who would bring in the covenant of faith -- the spiritual kingdom, with its doors open to every person - gathering believers (faith children of Abraham) from every nation under heaven.
God gave Abraham a 'sign' that would show who was under the blessing of this covenant and who was not. (Gen 17:7-14) The sign was circumcision -- remember this is still before God gave the law through Moses so circumcision has to do with Abraham, not the 'law', making it a piece of our gospel picture.
The shadow is physical circumcision -- anyone not circumcised was outside the blessing of the covenant and would be cut off ! The spiritual reality that this is pointing to , is the circumcision of our heart -- the 'circumcision' of our heart is the confirming sign that we are indeed children of Abraham - that we are under the blessings of the spiritual covenant of faith. (Col. 2:11)
Do you now see how the gospel was preached to and through Abraham? (and we could also have looked at the picture of Abraham offering his son, pointing to God offering His Son as the Lamb)
Do you realize the significance of this ?
Imagine that someone gives you the seed of a maple tree and tells you to plant it and then mark out on the ground the exact shape and size of the shadow the future full grown tree would cast. Could you do it ?? Impossible , isn't it ?
And yet that is what God has done , over and over again ... Marked out the shadow pointing in detail to the substance not yet a reality ... in fact being yet thousands of years in the future.
What amazing proof God has provided for us and with what confidence can we know that our God is indeed all-mighty and all-knowing to the nth detail. We can trust that His every word is true !
Our God is an awesome God !