What is Scripture but the word of God! To prove your case you need only show people getting saved without God's word -- that is without someone interpting God's word to someone with their own words, without God himself calling a person like in the case of Abraham, without another person sharing God's word with a person. And, that is impossible because,

Romans 2:11-16 "For there is no respect of persons with God. For as many as have sinned without law shall also perish without law: and as many as have sinned in the law shall be judged by the law; (For not the hearers of the law are just before God, but the doers of the law shall be justified. For when the Gentiles, which have not the law, do by nature the things contained in the law, these, having not the law, are a law unto themselves: Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another;) In the day when God shall judge the secrets of men by Jesus Christ according to my gospel."

Romans 3:23 For all have sinned, and come short of the glory of God;

Anyone who thinks they are going to heaven without repentance in Jesus are sadly mistaken.