One question I have concerning scripture is how does God authenticate his message? How do we know that it is really from him and not some kind of contrivance or fraud?
When God spoke to the Patriarchs and the prophets in the Old Testament he generally spoke directly. There was obviously something very clear about his presence, because the usual initial response was to fall on one’s face and proclaim your own unworthiness. Of course, even then one had to authenticate it to others. When Moses asked God how to do so, God provided him with miracles. It seems that this mode of authenticating God’s word is concentrated in two or three periods of time—the exodus, the divided kingdoms of Israel and Judah, and the first century AD. These correspond with the giving of the Law, the beginning of the fall of Israel, and the writing of the New Testament. Passages about the authentication of the New Testament include:
Therefore we ought to give the more earnest heed to the things which we have heard, lest at any time we should let them slip. For if the word spoken by angels was stedfast, and every transgression and disobedience received a just recompence of reward; how shall we escape, if we neglect so great salvation; which at the first began to be spoken by the Lord, and was confirmed unto us by them that heard him; God also bearing them witness, both with signs and wonders, and with divers miracles, and gifts of the Holy Ghost, according to his own will? (Hebrews 2:1-4)
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. (John 20:30-31)
And they went forth, and preached every where, the Lord working with them, and confirming the word with signs following. (Mark 16:20)
And he said unto them, Go ye into all the world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be damned. And these signs shall follow them that believe; In my name shall they cast out devils; they shall speak with new tongues; They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover. (Mark 6:15-18)
Of course, in the case of the New Testament, the ultimate miracle was the resurrection of Jesus. Paul pointed out to the Corinthians (1 Corinthians 15) that the resurrection was a clearly established fact, there being over 500 witnesses to it of whom, at that time, many were still alive and able to be questioned.
Since the message is complete, we have no need of further miracles or signs. They ended in the first or early second century because the signs that had been were written down.
The other way to authenticate a prophet’s message, when no miracles were present, was to see if it came true. “But the prophet, which shall presume to speak a word in my name, which I have not commanded him to speak, or that shall speak in the name of other gods, even that prophet shall die. And if thou say in thine heart, How shall we know the word which the LORD hath not spoken? When a prophet speaketh in the name of the LORD, if the thing follow not, nor come to pass, that is the thing which the LORD hath not spoken, but the prophet hath spoken it presumptuously: thou shalt not be afraid of him.” (Deuteronomy 18:20-23)