Yes, as Scriptures indicate. Both Christians and non-Christians - Muslims, Hindus, Buddhists, etc. - are part of the Body of Christ - the Lamb of God that takes away the sin of the world, the Lamb slain from the foundation of the world.
Christ carried the sins of the world in His Body on the cross (1 Pet 2:24) because God fashioned humanity (Jews & Gentiles - with all their sins) into Body of Christ on the cross, thereby creating the New Man: Christ - the Head, Humanity - the Body ( Eph 2:11-19). Hence, ALL died with Christ when He died (2 Cor 5:14, 15).
No wonder, Paul identified himself with the non-Christian Athenians as offspring or children of God:
Acts 17:28-29 28 "for in Him we live and move and have our being, as also some of your own poets have said, 'For we are also His offspring.' 29 "Therefore, since we are the offspring of God, we ought not to think that the Divine Nature is like gold or silver or stone, something shaped by art and man's devising.
This is why the gospel is good news for all, Christians and non-Christians alike.
But will all make it to life eternal? No, sir. Only overcomers will. Rev 3:5, 21; 21:27.