Henry M. Morris makes an excellent argument for the authenticity of the New Testament based on the testimony provided by it and history concerning the two major Christian ordinances:
Christian churches everywhere, of almost all denominations, practice two of the most remarkable ceremonies. Though the particular form of the observance of each may have changed in some respects with the passing years, the very fact of the observance is itself a strong testimony to the authenticity of the New Testament and Christianity. These two ceremonies are what are known as the ordinances of Baptism and the Lord’s Supper.
According to the Gospel records (e.g., Matthew 28:19) Baptism was commanded by Jesus Christ as an integral part of His Great Commission, to be given each new convert . . . Similarly observance of the Lord’s Supper was commanded by Him as a regular observance . . . (e.g., Matthew 26:26-28).
It is known, of course, from the literature of the church through the ages that the churches have always practiced these two ordinances in one form or another. The authority for doing so comes from the New Testament. However, the ordinances do have a peculiar witness of their own, not shared by the other events recorded in the New Testament.
As a matter of fact, they antedate the New Testament since they were established by Christ Himself and have been practiced ever since. It is clear from the book of Acts that converts always were baptized soon after conversion (Acts 2:41; 8:12; etc.). Also the churches regularly observed the Lord’s Supper (1 Corinthians 11:20-26), even before they had the New Testament Scriptures which commanded them to do so.
To appreciate the significance of this fact, one should try to imagine what it was like to be in one of these first century churches when they first began to receive copies of the epistles and other writings which eventually were to be the New Testament. Say, for example, it was a church which had been established as the result of the preaching of the Philip the evangelist. This church continued to exist, for, say, about twenty years after its founding before it began to receive copies of some of Paul’s epistles and perhaps another ten years before it obtained a copy of one of the four Gospels.
During this time it was guided in its practice by the teachings of its founder and perhaps also by other teachers whom God sent its way or raised up from its own members. Among the instructions they were following were, of course, those pertaining to Baptism and the Lord’s Supper. Philip, who had been one of the original seven deacons, would certainly have been careful to emphasize the basic importance of these two ordinances in the life of the church. When they finally received the actual written accounts of how those ordinances were first established, this would merely strengthen and confirm them in what they were already practicing and knew to be in accordance with the verbal teachings they had received at first.
But, now, just suppose neither Philip nor any of their other teachers had ever told them anything about either ordinance and they had not practiced either Baptism or the Lord’s Supper before, and neither had any of their sister churches with whom they had contact. Suddenly they receive a document purporting to be from an apostle (say, the Gospel of Matthew, or Paul’s first Epistle to the Corinthians) in which these ordinances are discussed in such a way as to indicate they had been established by Christ and practiced by the churches ever since.
The obvious reaction by the church would be to assume the documents were fraudulent and to reject them forthwith. Their authors obviously could not have been the real apostles, because they were proposing two ceremonies as having existed in the churches since the days of Christ Himself, which the church receiving the documents knew, from their own previous contacts, did not exist in the churches. Thus, these documents would have been rejected as spurious by this church and by any other churches to which they came.
Thus, at no time after the days of Christ, could any such writings ever have gained acceptance as authentic records at all, unless these ordinances which they described were actually being practiced in the churches at the time of their writing and circulation. In this way the very existence of the two simple ceremonies of Baptism and the Lord’s Supper, both picturing and commemorating the sacrifice of the Lord Jesus in obedience to His commandment, is in itself a powerful witness to the authenticity of the New Testament documents which describe their establishment and perpetuation. There is no way of accounting for the initiation of either of the ordinances except as described in these documents. The churches could never have been persuaded to begin practicing them by books or teachers who told them they had already been practicing them since the days of Christ, if in fact they knew otherwise. Therefore, the ordinances were established by Christ, and the New Testament writings which tell them about them are authentic.
Many Infallible Proofs: Evidences for the Christian Faith, 32-34; bold text is in italics in the original