9 That if you shall confess with your mouth the Lord Jesus (confess that Jesus is the Lord of Glory, and the Saviour of men, and that He died on the Cross that we might be saved), and shall believe in your heart that God has raised Him from the dead (pertains to the Bodily Resurrection of Christ, as is obvious), you shall be saved (it is that simple!).
10 For with the heart man believes unto Righteousness (presents the word “believing” in a mode of “thinking,” not of feeling; the “believing” has to do with believing Christ, and that His Sacrifice of Himself Atoned for all sin); and with the mouth confession is made unto Salvation (when Faith comes forth from its silence to announce itself and proclaim the Glory and the Grace of the Lord, its voice “is confession”).
11 For the Scripture says (combining parts of Isa. 28:16 with 49:23), Whosoever believes on Him (proclaims the fact that Salvation is reachable by all) shall not be ashamed (in essence says, “shall not be put to shame,” but rather will receive what is promised).
12 For there is no difference between the Jew and the Greek (should read, “between the Jew and the Gentile”; all must come the same way, which is by and through Christ and what He did at the Cross on our behalf): for the same Lord over all is rich unto all who call upon Him (the riches of Grace will be given to all who truly call upon the Lord).
13 For whosoever (anyone, anywhere) shall call upon the Name of the Lord shall be Saved (speaks of the sinner coming to Christ, but can refer to any Believer and with whatever need; the Cross is the means by which all of this is done).
1 John 1:9-10
9 If we confess our sins (pertains to acts of sin, whatever they might be; the sinner is to believe [Jn. 3:16]; the Saint is to confess), He (the Lord) is faithful and just to forgive us our sins (God will always be true to His Own Nature and Promises, keeping Faith with Himself and with man), and to cleanse us from all unrighteousness. (“All,” not some. All sin was remitted, paid for, and put away on the basis of the satisfaction offered for the demands of God’s Holy Law, which sinners broke, when the Lord Jesus died on the Cross.)
10 If we say that we have not sinned (here, John is denouncing the claims of sinless perfection; he is going back to Verse 8, speaking of Christians who claimed they had no sin nature), we make Him a liar (the person who makes such a claim makes God a liar, because the Word says the opposite), and His Word is not in us. (If we properly know the Word, we will properly know that perfection is not in us at present, and will not be until the Trump sounds.)