The promise is the Holy Spirit. Abraham would become a Father of many nations when spiritual children of all nations would be born as a result of his descendant according to the flesh - Christ.
Once again you just completely IGNORED this verse that tells us that the believers who lived under the Law were saved by grace:
"Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all" (Ro.4:16).
Evidently you have no answer to that so I guess that you are in the hope that it will just go away. I also said this:
The Jews who believed in the Lord Jesus' name were born of God when they believed:
"He came unto his own, and his own received him not. But as many as received him, to them gave he power to become the children of God, even to them that believe on his name: Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God" (Jn.1:11-13).
To this you said:
Complete nonsense!
When people believe in Jesus' name, they are accepting that it is through him alone that the benefits of the gospel message are received.
Even though the verse says clearly that it was those who believed in the Lord Jesus' "NAME" who were born of God you deny that truth.
Please tell me the gospel message which was being preached here:
And he sent them to preach the kingdom of God, and to heal the sick... And they departed, and went through the towns, preaching the gospel, and healing every where" (Lk.9:2,6).
We know that this is not the gospel which proclaims that Christ died for our sins because at that time of Luke 9 they didn't even know that Christ was to die:
"Then he took unto him the twelve, and said unto them, Behold, we go up to Jerusalem, and all things that are written by the prophets concerning the Son of man shall be accomplished...And they shall scourge him, and put him to death: and the third day he shall rise again. And they understood none of these things: and this saying was hid from them, neither knew they the things which were spoken" (Lk.18:31,33-34).
So tell me what gospel message which they were preaching.
It is only once a person is born of God or receives revelation, that they are able to accept that Christ is the Son of God. You have it back to front.
Of course you failed to address this passage which reveals that "life" comes as a "result" of believing that Jesus is the Christ, the Son of God:
"And many other signs truly did Jesus in the presence of his disciples, which are not written in this book: But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name" (Jn.20:30-31).
So we can understand that the "life" which those who believed in the identity of the Lord Jesus, that He is the Christ, the Son of God, was realized when they were born of God:
"Whosoever believeth that Jesus is the Christ is born of God: and every one that loveth him that begat loveth him also that is begotten of him. By this we know that we love the children of God, when we love God, and keep his commandments. For this is the love of God, that we keep his commandments: and his commandments are not grievous. For whatsoever is born of God overcometh the world: and this is the victory that overcometh the world, even our faith. Who is he that overcometh the world, but he that believeth that Jesus is the Son of God?" (1 Jn.5:1-5).
Which obviously means he was no longer under the law after believing in Jesus, and this goes against mad.
No, Peter believed that Jesus is the Christ, the Son of God, during the Lord's ministry (Mt.16:16) and therefore he received new life when he was born of God. And despite what you say he continued living under the law.
Since Peter believed that Jesus is the Christ, the Son of God, he was no longer under the demands of the law in regard to establishing his own righteousness:
"For Christ is the end of law for righteousness to every one that believeth" (Ro.10:4).
You even admit that Peter was saved by grace and we know that "grace" and "works" are mutually exclusive:
"For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast" (Eph.2:8).
"Now to him that worketh is the reward not reckoned of grace, but of debt" (Ro.4:4).
Now a question for you, Andy. We know that the Jews who lived under the law were saved during the ministry of the Lord Jesus (Jn.1:11-13;Lk.7:49). Were they saved by grace through faith? Let me give you a little hint:
"Therefore it is of faith, that it might be by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all" (Ro.4:16).