Gal. 4:4-5 ... "When the fullness of the time came, God sent forth His Son, born of a woman, born under the Law, so that He might redeem those who were under the Law, that we might receive the adoption as sons."
The purpose of Jesus in coming to earth was to redeem fallen man. In the beginning God created man in His Own image (Gen. 1:27), but after the passing of several millennia man was so changed by sin that he retained little resemblance to his Creator. When Adam ate of the forbidden fruit, sin invaded the world and soon permeated all of human experience. We are told in Romans 5 that "through one man sin entered into the world" (v.12) and that "through the one man's disobedience the many were made sinners" (v.19). As the centuries passed and sin gained an ever stronger grip on the human soul, man came more desperately to need someone to save him from his wretched condition. Paul spoke for every sinner when he cried in Rom. 7:24, "Who will set me free from the body of this death?" The answer, of course, was (and still is) Jesus Christ. Even as men daily sold themselves further into debt to sin, God was planning the means for their salvation. Man had nothing valuable enough to purchase the liberty of his own soul, but God did -- the life of His only Son.
The text above refers to God's plan and reveals that it was developed, not in a day, but over a long span of time. It says, "When the fullness of the time came." This indicates a prolonged process of development and actually expresses the Biblical view of history from the Creation up to the birth of Christ. In general, the things that were happening in the world over the course of millennia past had a common thread running through them. As nations and empires rose and fell, as ethnic groups migrated from place to place, as one civilization replaced another at a higher level of culture, as technologies gradually improved, the hand of God was busy, unseen by human vision and unimagined by the most gifted thinkers, God as the Supreme Engineer was crafting the state of the world to the right condition to receive His Son as its Redeemer.
It has been observed that three great achievements among men in the few centuries just previous to Jesus' coming had especially prepared conditions for Christ and His mission. First, Jews had scattered over most of the civilized world with the Mosaic Law and the concept of one true God. In most cities a synagogue of Jews had laid a foundation of faith in God upon which Christian evangelists would later build. Second, the Romans had conquered most of the known world and established the Pax Romana, the Roman Peace. Highways and sea lanes were cleared of bandits, cutthroats, and thugs, so that when Christian ministers took the gospel to foreign lands, they were able to travel safely without hindrance. Also, Roman civil engineers had constructed marvelous viae, the ancient super highways. Paul and others used them to travel quickly and directly from one great city to another. Third, in the aftermath of the conquests of Alexander the Great, the Greek language had been introduced as the lingua franca in most areas. Language scholars claim that this language was perhaps the most precise for conveying intellectual concepts that men have ever spoken. It is little wonder that just when it was time for the gospel to be reduced to Scripture as the New Testament, it was this language that was available for its inscription. It is not coincidental that these three great human achievements were at the zenith of their development when God entered into human flesh as a little Baby in the Judean village of Bethlehem. The invisible hand of God was shaping the design of these things so that they could be used in an optimum way to present Christ and His gospel of redemption to the world. The result, which today is still astounding and almost incredible, is that it could be said that within a generation "the gospel ... was proclaimed in all creation under heaven" Col. 1:23. All who were willing then had the opportunity to be redeemed and have had it from that time to this.
