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Why Be A Christian? (3a)

This is a seven-part series on why everyone should be a Christian.
Click on the following links to explore the various installments:

(3) The Credibility of Christ

[a] Evidence From John 5

Jesus of Nazareth made many extraordinary claims. But all the claims in the world are meaningless if the evidence does not back them up. “If I do not do the works of my father,” Jesus said, “do not believe me” (Jn. 10.37).

Indeed, the Christian faith is grounded in "certainty" (Lk. 1.4) — not mere guesswork or leaps in the dark, which leave room for doubt (cf. Jm. 1.6). There are many "infallible proofs" (Acts 1.3), which confirm the message we must share (Mk. 16.20).

When Paul presented the case for Christ, he said he was speaking “the words of truth and reason” (Acts 26.25) — not fable or wishful thinking. Jesus himself said we can "know the truth" (Jn. 8.32). Christians are instructed to "prove all things" (1 Th. 5.21). And Scripture frowns upon believing something/someone without adequate evidence (cf. 1 Jn. 4.1).

In that light, what evidence supports Jesus’ claims?

In part two, I explored the profile evidence — viz., Jesus’ character was consistent both with his claims and with the nature of deity.

Now, let us inspect the external evidence — i.e., outside of Jesus’ personality. In this installment particularly, we shall examine Jesus’ dialogue with his detractors in John 5.

In this context, Jesus made two of his many audacious claims:

(1) He has the authority to give life, both spiritual and material (Jn. 5.21, 24-26, 28-29).

(2) He has the authority to judge the world (Jn 5.22, 27, 29).

After making these claims, Jesus acknowledges that his own testimony — however accurate and important (cf. Jn. 8.14) — is inconclusive by itself (Jn. 5.30-31; cf. Deut. 19.15). So he next demonstrates that he was “not alone” in testifying to the veracity of his claims (cf. Jn. 8.16-18).

Consider the evidence our lord submits in this chapter.

John The Immerser

First, the prophet John testified about Jesus (Jn. 5.32-36a).

Everyone — including the wicked Herod — knew that John was a “just and holy man” (Mk. 6.20). The secular historian Josephus (cir. 37-100 A.D.) described him as “a good man” (Antiquities 18.5.2). Even the Pharisees “were willing for a time to rejoice in his light” (Jn. 5.35), acknowledging that “all count John as a prophet” (Mt. 21.26). The immerser had all the credentials of a “man sent from God” (Jn. 1.6; cf. Lk. 20.4).

John was sent to be the “voice” that prepared the way for the coming of the “glory of the Lord” (Isa. 40.3-5; cf. Jn. 1.22-23). As such, he was not interested in drawing people to himself — he was just the “voice,” not the “glory” — but to the one who came after him (Jn. 1.15, 27).

Even before John immersed Jesus, he was aware of his relative’s moral greatness, initially refusing to immerse him (Mt. 3.14; cf. Lk 1.36). However, it was not until God gave him a sign after the immersion that John “knew” (oida—to perceive definitively by his own experience) that Jesus was the Messiah (Jn. 1.31-34; cf. Mt. 3.16-17). What once may have been a suspicion about Jesus — due to his moral superiority over him — was now irresistible in John’s mind.

Thereafter, John began informing the people — long before Jesus became a public figure, and even longer before he made his audacious claims — that Jesus was “the lamb of God who takes away the sin of the world” (Jn. 1.29). He “bore witness” that Jesus was indeed the Christ, anointed by the Spirit, who was greater both in authority and in worthiness (Jn. 1.7-8, 15, 19-27, 32; Mk. 1.7). As a spokesman for God, he testified that Jesus is “the Son of God” (Jn. 1.34; cf. Mt. 3.17), who, though younger than John, “existed before” him (i.e., in eternity; Jn. 1.15, NET).

Thus, John gave the Jews dispassionate testimony, independent of Jesus’ claims about himself, which pointed not to himself but to the glory of Jesus (Jn. 1.20, 27; 3.28; cf. Jn. 1.14-15).

In giving this testimony to the public, the prophet’s influence and ministry began to wane (cf. Jn. 3.30). He quickly fell under the scrutiny of the authorities, the pressure of which never moved him. Eventually, his integrity was on full display when, though threatened for denouncing Herod’s lawless marriage, he refused to recant, which lead to his beheading (Mk. 6.16ff). Hence, John proved to be a conscientious man, even when his testimony cost him his life.

It is an understatement, then, to say that John was a trustworthy witness.

However, as important and “true” as John’s testimony was, Jesus noted that there were even better witnesses than him (Jn 5.36a; cf. 1 Jn. 5.9).

The Works Of Jesus

Second, the miraculous works he performed demonstrate that he was sent by God (Jn. 5.36b).

A miracle is an event that cannot be produced by the natural or scientific order, which can only be attributed to the agency of God (see Lindberg, p. 860).

The miracles of Jesus, therefore, were powerful demonstrations designed to corroborate his claims of deity (cf. Mk. 16.20). “No one can do these signs that You do,” Nicodemus confessed to Jesus, “unless God is with him” (Jn. 3.2; cf. Jn. 10.25, 38).

In addition to all his supernatural acts of healing mentioned previously (part two), Jesus also stopped raging storms with only a word (Mt. 8.23-27), walked on about “three or four miles” of water in the “middle of the Lake” of Galilee (cf. Mk. 6.47ff; Jn. 6.15-21), turned water into wine (Jn. 2.1-11), miraculously caught two boat-loads of fish on the Lake of Gennesaret (Lk. 5.1-11; cf. Jn. 21.4-11), miraculously knew that the first fish Peter caught would produce a coin for them to pay the temple tax (Mt. 17.27), withered a fig tree instantly (Mt. 21.18-19), etc.

All these wondrous works were performed in the presence of thousands of eyewitnesses. “This thing was not done in a corner” (Acts 26.26)! Any one of his miracles could have been falsified. Yet, not even his enemies could deny their reality (Jn. 11.46-47; Lk. 5.26; cf. Acts 4.16).

Though Jesus worked many other miracles, those that were written were documented by eyewitnesses to establish the validity of his claims (Jn. 20.30-31). Like John, these eyewitnesses suffered and died maintaining that their testimony was what really happened. Concerning these eyewitnesses, Professor Paul Little (1928-1975) poignantly asked:

“Are these men who helped transform the moral structure of society consummate liars or deluded madmen?” (Little, p. 63)

Neither alternative is consistent with the ethic they lived and espoused, nor with the influence they have wielded over the world. Indeed, the notion that they were either liars or madmen is

“harder to believe than the fact of Jesus, the incarnation of God rising from the dead” (ibid.).

Professor Bruce Metzger (1914-2007) observed:

“If it were true, as some have suggested, that the evangelists invented the stories of Jesus’ miracles, it is passing strange that they overlooked many an opportunity where pious imagination might well have embroidered the narrative. On the contrary, sometimes the evangelist’s account is told in such matter-of-fact style, stripped bare of all embellishments, that the reader cannot be certain whether a miracle is intended or not (as, for example, Jesus’ escape from the angry mob, reported in Luke 4.30)” (Metzger, pp. 133-134).

Indeed, not only did they not embellish the miracles they documented, the gospel writers wrote about them relatively sparingly. Metzger noted that these eyewitnesses did not exhibit “an insatiable craving for the miraculous” (ibid., p. 133). They were not interested in mere sensationalism, but chiefly in reason, in dialogue, in evidence, in history, presenting Jesus as

“one who refuses to perform mighty works merely for the sake of a spectacle (Mt. 12.38-39; Mk. 8.11-12; Lk. 11.29; 23.8-9)” (ibid., p. 134).

In short, the eyewitnesses simply reported what they saw, touched, and heard, without embellishment or imbalance. For this testimony, they sacrificed everything.

The Father Himself

Third, the heavenly father himself testified about Jesus (Jn 5.37-38; cf. Jn. 8.18).

The father testified in two ways:

(1) Through direct audible communication;

(2) Through the Scriptures.

In the first category, the father’s voice pealed from heaven at Jesus’ baptism, saying: “This is My beloved Son, in whom I am well pleased” (Mt. 3.17).

At the mount of transfiguration, Peter, James, and John testified that they heard the father’s voice in the cloud that overshadowed them saying the same thing, adding: “Hear him” (Mt. 17.5).

During his final triumphal entry into Jerusalem, several people heard the “voice” of the father speak to Jesus “from heaven” (Jn. 12.28f).

What more powerful testimony is there than the very voice of God thundering from the clouds?

However, Jesus noted that the Pharisees never “heard his voice” (Jn. 5.37). Nor had they listened to the father’s word in the Scriptures well enough to believe his testimony about Jesus, for those very Scriptures spoke about him (Jn. 5.38). Hence, they have never accepted the father’s testimony, whether audible or written!

The Prophecies of Scripture

This leads us to the next piece of evidence. Jesus noted that the inspired prophecies of Scripture testified about him (Jn 5.39-47).

The messianic prophecies in the Old Testament are numerous and detailed. Risto Santala — a scholar in the fields of Judaism and rabbinic literature — wrote that

“the Old Testament contains altogether some 456 prophecies concerning Christ. Of these 75 are to be found in the Pentateuch, 243 in the Prophets, and 138 in the ‘Writings’ and Psalms” (Santala, p. 149).

Consider a succinct list of a few of these prophecies:

The Messiah shall be a male (Isa. 9.6), born of a virgin (Isa. 7.14) in the small town of Bethlehem (Micah 5.2). He shall come from the lineage of Jacob (Num. 24.17), Judah (Gen. 49.10), and David (Isa. 9.7). He shall be a prophet (Deut. 18.15); more than that, he shall be the Son of God, worthy of worship (Ps. 2.7, 12). He shall be a healer of the deaf and blind (Isa. 29.18-19). He shall reign as a lowly but exalted king (Zech. 9.9), whom the people and their rulers shall reject (Ps. 2.1-2; Isa. 53.1ff). His own familiar friend shall betray him (Ps. 41.9) for thirty pieces of silver (Zech. 11.13). He shall not respond to those who accuse him falsely (Isa. 53.7). He shall be ridiculed (Ps. 22.7-8), spat upon (Isa. 50.6), given vinegar (Ps. 69.21). His hands and feet shall be pierced in the manner of crucifixion (Ps. 22.16). He shall be killed alongside criminals (Isa. 53.12) — a sacrifice for the sins of humanity (Isa. 53.5, 8, 10, 12) — and buried in a rich man’s tomb (Isa. 53.9). However, he shall not stay dead long enough for his body to experience decay, for he shall be resurrected (Ps. 16.10) and shall ascend to God’s right hand (Ps. 110.1). According to Daniel (c. 600 years before Christ), “the Messiah” shall be “cut off” around 30 A.D. (Dan. 9.25-26).

The prophecies concerning the Messiah in the Old Testament are so staggering in detail that one could easily put together a biography of Jesus without consulting a single verse in the New Testament! From an exhaustive study of these prophecies, Free and Vos reason that

“the chances of all these prophecies being fulfilled in one man are so overwhelmingly remote that there is no way they could be the shrewd guesses of mere men” (Free and Vos, p. 242).

Kyle Butt and Eric Lyons conclude:

“When all of the pieces of the Messianic puzzle are put together, one individual stands out as the only person who fulfilled every single prophecy in minute detail — Jesus Christ. The life and activities of Jesus Christ as recorded in the New Testament documents blend the theme of a regal monarch and a suffering servant into one magnificent portrait of the triumphant Lion of Judah in His resurrection from the grave” (Butt and Lyons, p. 97).

Thousands of people “witnessed” Jesus “fulfill” each of these prophecies (cf. Lk. 24.44-48). So unimpeachable was their testimony that within a single generation, the Christian faith had spread throughout the entire Roman empire and beyond (Col. 1.6, 23).

The Resurrection

Finally, Jesus does not mention his resurrection as evidence of his claims in John 5. However, he does on another occasion.

In Matthew 12.38 the scribes and Pharisees wanted to see a supernatural “sign” that Jesus was who he claimed to be. He responded:

“An evil and adulterous generation seeks after a sign, and no sign will be given to it except the sign of the prophet Jonah. For as Jonah was three days and three nights in the belly of the great sea creature, so will the Son of Man be three days and three nights in the heart of the earth” (Mt. 12.39-40).

Jesus was referring to his imminent death, burial, and resurrection, when he would be buried “in the heart of the earth” for three days and resurrected on “the third day” (Mt. 16.21). This “sign of the prophet Jonah” is, as John Locke put it,

“the great and demonstrative proof of his being the messiah” (Locke, p. 340).

“As a historic fact,” observed W. J. Sparrow-Simpson,

“it has been his resurrection that has enabled men to believe in his official exaltation over humanity. It is not a mere question of the moral influence of his character, example, and teaching. It is that their present surrender to him as their redeemer has been promoted by this belief, and could not be justified without it” (Sparrow-Simpson, pp. 513-514).

Indeed, if Jesus is still dead, there would be no reason to be a Christian. Our faith would be “vain” (1 Cor. 15.14-19). Why should we follow an imposter whose exalted claims came to nothing? What use is a dead savior?

But if he was resurrected, his claim of being the “Son of God with power” over life and death would be demonstrably proven (Rm. 1.4).

Since the resurrection of Christ is so vital to Christianity, it is worth examining more thoroughly. However, to keep these studies succinct, I will publish the study of the resurrection of Christ in two subsequent installments.


Why not keep studying? Move on to part 3b:

Butt, Kyle and Eric Lyons. Behold! The Lamb of God. Montgomery, AL: Apologetics Press, Inc., 2006.

Free, Joseph P. and Howard F. Vos. Archaeology and Bible History. Grand Rapids, MI: Zondervan, 1992.

Lindberg, Christine A. (ed.). The Oxford American College Dictionary. New York: G. P. Putnam’s Sons, 2002.

Little, Paul. Know Why You Believe. Downers Grove, IL: IVP Books, 2008.

Locke, John. The Works of John Locke, In Ten Volumes, Vol. 7. London: T. Davison, 1812.

Metzger, Bruce M. The New Testament: Its Background, Growth, and Content, 2nd edition. Nashville, Abingdon Press, 1988.

Santala, Risto. The Messiah in the Old Testament: In the Light of Rabbinical Writings, William Kinnaird (trans.). Jerusalem, Israel: Karen Ahvah Meshihit, 1992.

Sparrow-Simpson, W. J. “Resurrection and Christ,” in A Dictionary of Christ and the Gospels: Vol. 2, James Hastings (ed.). Edinburgh: Clark, 1908.



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