A Second Witness
Besides the witness of fulfilled prophecy, there is second witness to the Bible's claim that it is God's Word: the unity of scripture. Though comprised by many men over some two thousand years, the Bible is, in fact, one book with one dominant theme. From start to finish, it revolves around the revelation of the person and work of Jesus Christ, the Son of God.
No sooner do our first parents fall prey to Satan and sin but God promises a Deliverer (Gen. 3:15). Later, God promises that all the families of the earth would be blessed through a descendent of Abraham (Gen. 22:18). In those bloody, animal sacrifices, given to Israel through Moses at Sinai, we trace the shadowy outlines of God's plan of salvation. We see forgiveness coming through the means of a substitute standing in the place of guilty ones, receiving the judgment their sins have merited. Arriving at David's day, the identity of this promised One is further refined. God promises that a descendent of David will reign upon his throne forever and ever (II Sam. 7:12-13). In the Psalms further details are added concerning the life of this coming One, including His betrayal (Psa. 41:9), the events surrounding His death (Psa. 22), and His resurrection (Psa. 16:9-10). The prophets even more clearly foretell His ministry. That remarkable fifty-third chapter of Isaiah speaks plainly of Him bearing the sis of His people and of the salvation obtained thereby. The Old Testament ends with Malachi's prophecy of a forerunner coming to prepare the way for the promised One (Mal. 3:1).
The New Testament begins with the appearance of this forerunner, John the Baptist (Mark 1:1-4), and then of the Messiah Himself, Jesus of Nazareth. In the Gospels, we follow the course of His life, marveling at His words and wondering at His works. We behold His death, burial, resurrection, and ascension to glory, seeing ancient prophecies fulfilled at every juncture (e.g. John 19:24, 28, 36-37). In Acts, we see His ministry continuing through the affusion of His Spirit upon His church. In the Epistles, we see His Apostles completing His instruction to His people as to their faith and practice. Finally, in the Revelation, we see Him bring about the consummation of the age.
The Bible, in its consistency and unity, bears witness that it is indeed "the record that God gave of His Son!"