Amen. Scripture is the means by which God has chosen to dispense His saving grace through faith in Jesus Christ. I suppose He could do it some other way, but so far, He hasn't.
That all men should honour the Son, even as they honour the Father. He that honoureth not the Son honoureth not the Father which hath sent him. Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life." -- John 5: 22-24."For the Father judgeth no man, but hath committed all judgment unto the Son:
Thus you're correct, IOTN, when you reference the Great Commission where Jesus instructed all Christians to preach the word of God to all nations and races so that all whom God has given to Christ will be brought home.
Salvation's not a game of chance. All whom Christ was sent to redeem will be redeemed. God is not surprised by any face He sees in heaven.
My dispensational leaning prompted me to respond here. Scripture is certainly the mainstay to doctrine in this dispensation, however it was not the first means that God chose, nor do I believe that it will be the last.
God began dispensing grace in the garden when he killed animals instead of Adam and Eve. I think that Adam and Eve had some measure of understanding of grace, perhaps greater than we have today. Though they did not know Jesus, the man, they were looking ahead for him.
Scripture was added much later.