One of the most amazing ‘pictures’ of the of the Gospel message in scripture is found in the last book of the Bible:

Then I saw a Lamb, looking as if it had been slain, standing in the center of the throne, encircled by the four living creatures and the elders. He had seven horns and seven eyes, which are the seven spirits of God sent out into all the earth. He came and took the scroll from the right hand of him who sat on the throne. And when he had taken it, the four living creatures and the twenty-four elders fell down before the Lamb. Each one had a harp and they were holding golden bowls full of incense, which are the prayers of the saints. And they sang a new song:

“You are worthy to take the scroll
and to open its seals,
because you were slain,
 and with your blood you purchased men for God
from every tribe and language and people and nation.”

Revelation 5:6-9

With the currency of His own blood, the coin of the Heavenly Realm, Christ purchased men for God. Other translations use terms like ransomed, redeemed, or bought. Regardless of the specific term, what happened at Calvary was as firm a transaction as walking into a store, placing money on the counter and walking out with whatever you intended to buy. Only in terms of fallen men, the Father sent his Son to earth to ‘buy back for himself’ (Christ purchased men for God), out of the mass of fallen humanity, men and women from every ‘people group’ on the planet

The Apostle Paul, everywhere he went and to every audience, spoke a simple message of Christ and him crucified (1 Cor 2:2). Paul also very specifically defined the core of the gospel message – that Christ died for our sins (1 Cor 15:1-4).

The passage in Revelation and Paul’s gospel provide slightly different perspectives of the same message.  In Revelation we have the ‘big picture’. In Paul’s letter to the Corinthians, as well as in the entire body of his preaching, we have the gospel message that is to be the center of the ‘good news’ we are to declare to all men.