I agree and disagree. (So what, right? 
)
For all who have sinned without the Law will also perish without the Law, and all who have sinned under the Law will be judged by the Law; 13 for it is not the hearers of the Law who are just before God, but the doers of the Law will be justified. 14 For when Gentiles who do not have the Law do instinctively the things of the Law, these, not having the Law, are a law to themselves, 15 in that they show the work of the Law written in their hearts, their conscience bearing witness and their thoughts alternately accusing or else defending them, 16 on the day when, according to my gospel, God will judge the secrets of men through Christ Jesus.
I think your Muslim scenario plays out within these verses in Romans as well aas John 3:7
However, I still believe all men need a sacrifice, everyone. But I believe their righteousness testifies that they did receive it** in the secret place of their heart**… and will rejoice to see Him, as you postulated, on that Day where the one they knew in their conscience will become manifest unveiled and approve the testimony of their deeds and the secrets of their hearts.
Most people do not know what a Samaritan was(Luke 10:25-27). They were the most ignorant and detestable of people to the Jews, worshipping pagan Baals and YHWH in the same temple. The parable known as the good Samaritan also presents this aspect of the testimony of “unknowledgeable”(theologically, creedally) righteousness through deeds bearing witness to justification in earthly life and on the Day.
The Pharisee and the Levite were convicted by their deeds in spite of their outward costume(literal and metaphysical/spiritual). And we are never told what nationality, heritage or creed the wounded man is. he is simply “my neighbor”(“As you have done it to the least of these, you have done so to me”)
Most people don’t know what sacrifice is, in terms of the cross. It is all about practicaly expressed love, as in Matthew 25:31-46
31 “But when the Son of Man comes in His glory, and all the angels with Him, then He will sit on His glorious throne. 32 All the nations will be gathered before Him; and He will separate them from one another, as the shepherd separates the sheep from the goats; 33 and He will put the sheep on His right, and the goats on the left.
34 “Then the King will say to those on His right, ‘Come, you who are blessed of My Father, inherit the kingdom prepared for you from the foundation of the world. 35 For I was hungry, and you gave Me something to eat; I was thirsty, and you gave Me something to drink; I was a stranger, and you invited Me in; 36 naked, and you clothed Me; I was sick, and you visited Me; I was in prison, and you came to Me.’ 37** Then the righteous will answer Him, ‘Lord, when did we see You hungry, and feed You, or thirsty, and give You something to drink? 38 And when did we see You a stranger, and invite You in, or naked, and clothe You? 39 When did we see You sick, or in prison, and come to You?’ 40 The King will answer and say to them, ‘Truly I say to you, to the extent that you did it to one of these brothers of Mine, even the least of them, you did it to Me.’**
41 “Then He will also say to those on His left, ‘Depart from Me, accursed ones, into the eternal fire which has been prepared for the devil and his angels; 42 for I was hungry, and you gave Me nothing to eat; I was thirsty, and you gave Me nothing to drink; 43 I was a stranger, and you did not invite Me in; naked, and you did not clothe Me; sick, and in prison, and you did not visit Me.’ 44 Then they themselves also will answer, ‘Lord, when did we see You hungry, or thirsty, or a stranger, or naked, or sick, or in prison, and did not take care of You?’ 45 Then He will answer them, ‘Truly I say to you, to the extent that you did not do it to one of the least of these, you did not do it to Me.’ 46 These will go away into eternal punishment, but the righteous into eternal life.”
Yet, the Lamb was slain from the foundation of the world, and one of those secrets of the heart thatr produces that love, forgiveness, compassion is the knowledge of our own weakness, and the frailty of our own righteousness…
“In each of us the fabric of integrity is frayed
The torn and tattered edges of our weaknesses displayed
But when our grand delusions are by honesty betrayed
Integrity, once shaken- by humility is stayed.”
The Psalmist delves into this deeply in many places… being a man after Gods own heart yet aware of His need for forgiveness, and the frailty of His own righteousness.
"Behold, you desire truth in my innermost parts
You will teach me wisdom in my hidden places "
“A broken and a contrite heart you will in know wise cast out”
Purge me with hyssop and I will be clean
Wash me and I will be whiter than snow.
Surely I was sinful at birth, sinful from the time my mother conceived me."
But there is, in my opinion, no contradiction between the universal need for the Lamb slain from the foundation of the world, and the justification of the righteous but “unknowledgeable”. One of these works of righteousness is humility. Another forgiveness.
Hebrews 4:3 Now we who have believed enter that rest, just as God has said, “So I declared on oath in my anger, ‘They shall never enter my rest.’” And yet his works have been finished since the creation of the world.
The word finished here is so imortant because it was all finished before it played out, and that testimony, according to Paul AND John is hidden in EVERY HEART.
For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men who suppress the truth [l]in unrighteousness, 19 because that which is known about God is evident within them; for God made it evident to them. 20 For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.
9 The true light that gives light to everyone was coming into the world.
The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by human hands. 25 And he is not served by human hands, as if he needed anything. Rather, he himself gives everyone life and breath and everything else. 26 From one man he made all the nations, that they should inhabit the whole earth; and he marked out their appointed times in history and the boundaries of their lands. 27** God did this so that they would seek him and perhaps reach out for him and find him, though he is not far from any one of us. 28 ‘For in him we live and move and have our being.’ As some of your own poets have said, ‘We are his offspring.’**
Paul spoke in an inclusive “we” to the assembled pagan philosophers in Athens, turning them from idolatry to the worship of the living God. This deos not mean they did not need “the Lamb slain”. The world was created through the Lamb slain, and everyone who believes enters that rest, and many know in their hearts tho they may be in the dark about it in their minds… Just as many Christians and Jews think they are in the light about it in their minds, but their deeds testify otherwise, because they do not understand humility and practical love- which what the cross is ALL ABOUT… SIMPLE PRACTICAL LOVE. "
“No greater love has a man than this that He lay down His life for a friend”… It is in that love that the blood(life- spiritual/metaphysical) of Christ flows, and He will see to the core of every heart on the Day as Paul says,
14 For when Gentiles who do not have the Law do instinctively(physei-by nature) the things of the Law, these, not having the Law, are a law to themselves, 15 in that they show the work of the Law written in their hearts, their conscience bearing witness and their thoughts alternately accusing or else defending them, 16 on the day when, according to my gospel, God will judge the secrets of men through Christ Jesus.
Conscience/consciousness- hidden places- innermost heart, nothing new here to the Psalmist 2000 years before Christ. Evident by nature to the man after God’s heart, who forsees the sacrifice prophetically and embraces it as the blood shed on the mercy seat, “It Is Finished”.
So the teaching of the universal sacrifice does not actually contradict the righteous unknower who instinctively know and acts accordingly and is justified by God BECAUSE IT IS ABOUT LOVE AND UNION WITH IT AS THE FOUNDING PRINCIPLE OF THE UNIVERSE.
Christ broke the veil for this love and as Paul says again to Timothy…
“The foundation of God is sealed with this inscription, Lord knows them that are His and let everyone who names the name of the Lord depart from iniquity”,
which is totally consistent with Romans 2:14-21
The Lord know them that are His
For when Gentiles who do not have the Law do [n]instinctively the things of the Law, these, not having [o]the Law, are a law to themselves, 15 in that they show the work of the Law written in their hearts, their conscience bearing witness and their thoughts alternately accusing or else defending them, 16 on the day when, according to my gospel, God will judge the secrets of men through Christ Jesus.
Let everyone who names the name of the Lord depart from iniquity
17 But if you bear the name “Jew” and rely upon the Law and boast in God, 18 and know His will and [q]approve the things that are essential, being instructed out of the Law, 19 and are confident that you yourself are a guide to the blind, a light to those who are in darkness, 20 a corrector of the foolish, a teacher of the immature, having in the Law the embodiment of knowledge and of the truth, 21 you, therefore, who teach another, do you not teach yourself?
Sorry if I say too much, but my opinion is that any debate about a conflict between teachng the sacrifice of Christ and the crack in man’s nature that sacrifice heals- as an impediment to justification for righteous unbelievers/unknowers- is a straw man. Both the knowers and the unknowers have had that testimony in their deepest place since the beginning. It is how everyone knows they ought to help and love and give, whether they do or not. It’s the testimony of love. And it is the Lamb slain.
