Romans 10:12 (KJV)

Or, Who shall descend into the deep? (that is, to bring up Christ again from the dead.)

But what saith it? The word is nigh thee, even in thy mouth, and in thy heart: that is, the word of faith, which we preach;

That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.

For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.

For the scripture saith, Whosoever believeth on him shall not be ashamed.

For whosoever shall call upon the name of the Lord shall be saved.

How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher?

And how shall they preach, except they be sent? as it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things!

But they have not all obeyed the gospel. For Esaias saith, Lord, who hath believed our report?

So then faith cometh by hearing, and hearing by the word of God.