Given that Matthew summarizes the response to the Sermon on the Mount by saying that the crowds were astonished at Jesus’s teaching (Matthew 7:28-29)- – and remembering that the Gospel concludes with Jesus saying, “All authority has been given to me (Matthew 28:18) – – any study on the Sermon on the Mount needs to consider the authority of Christ.
As I noted earlier in this series of posts, currently I am preaching through the Sermon on the Mount. Our time on Sunday mornings is limited so I am also making my study notes available. Bear in mind that these are simply my notes and are not particularly well organized and certainly not edited. Some of the material is technical. Previously I posted my notes on the Kingdom of Heaven and Matthew’s use of inclusio / bracketing.
Authority (ἐξουσία /exousia) – “The right to control or govern over” (Louw and Nida).
Matthew concludes the Sermon on the Mount (Matthew 7:28-29) by observing that the crowds were astonished at Jesus’s authority. This summary statement demonstrates that a great deal of attention should be given to what is meant by Christ’s authority. Ultimately we will see Jesus’s incredible yet true claim that his authority rested in Himself and was not derived like that of the Scribes.
But first, we should consider the reaction to Christ’s authority. Matthew’s gospel says that the on looking crowds were “astonished.” The word translated “astonished” means to be so amazed as to be practically overwhelmed. My paraphrase is that those who heard the Sermon on the Mount were “blown away.” It helps gauge the level of the crowds astonishment at Jesus’s authority to observe how the word translated “astonished” in Matthew 7:28 is used by Luke in Acts 13:12. In Acts 13 when a man is struck blind after opposing the early church. Luke gives the following account.
 So, being sent out by the Holy Spirit, they went down to Seleucia, and from there they sailed to Cyprus.  When they arrived at Salamis, they proclaimed the word of God in the synagogues of the Jews. And they had John to assist them.  When they had gone through the whole island as far as Paphos, they came upon a certain magician, a Jewish false prophet named Bar-Jesus.  He was with the proconsul, Sergius Paulus, a man of intelligence, who summoned Barnabas and Saul and sought to hear the word of God.  But Elymas the magician (for that is the meaning of his name) opposed them, seeking to turn the proconsul away from the faith.  But Saul, who was also called Paul, filled with the Holy Spirit, looked intently at him  and said, “You son of the devil, you enemy of all righteousness, full of all deceit and villainy, will you not stop making crooked the straight paths of the Lord?  And now, behold, the hand of the Lord is upon you, and you will be blind and unable to see the sun for a time.” Immediately mist and darkness fell upon him, and he went about seeking people to lead him by the hand.  Then the proconsul believed, when he saw what had occurred, for he was astonished at the teaching of the Lord. (Acts 13:4-12 ESV)
Luke uses the same word to describe the astonishment of the on looking Sergius Paulus, “a man of intelligence,” who had summoned Barnabas and Saul to hear the Word of God.
In reading the Gospel of Matthew, we begin to be astonished with Jesus’s authority even in the way that Matthew presents Christ leading up to the Sermon on the Mount. Matthew’s gospel:
- Begins by tracing Jesus’s genealogy demonstrating that he is the culmination of the whole flow of the Old Testament.
- Continues by showing how Jesus is the fulfillment of prophecy
- Brings Moses to mind by showing how both Moses and Jesus were threatened as infants (Exodus 2:1-10, Matthew 2:16-18).
- Emphasizes that Jesus comes out of Egypt like Israel
- Leads up to the Sermon on the Mount with Jesus’s victory in the wilderness.
As the Sermon on the Mount begins, Jesus goes up on the mountain. Matthew’s Jewish readers would have seen a parallel between Jesus going up on the mountain and Moses who went up on the mountain to receive the 10 commandments. As noted above, Jesus has already been paralleled with Moses in that both their lives were threatened as infants (Exodus 2:1-10, Matthew 2:16-18).
Further, the idea of Jesus sitting down with people coming to hear him teach also stressed his authority. Jesus opens his mouth – there is a split second of suspenseful silence – and Jesus begins to speak.
In the content of his Sermon on the Mount, Jesus’s authority expressed itself in several ways.
- Christ spoke as the authority rather than appealing to policies. Notice his repeated use of the saying, “Truly I say to you” (ἀμὴν λέγω ὑμῖν/ amen legō humin) (5:18, 6:2, 5, 16, 25, 29) and “But I say to you” (ἐγὼ δὲ λέγω ὑμῖν) (5:22, 28, 32, 34, 39, 42) – Jesus’s use of these two phrases demonstrates how he took a posture of unique and divine authority. The latter phrase, “but I say to you,” appears six times as noted and is used in each case to clarify the meaning of the law and to show how the scribes and Pharisees had missed the heart of the matter. Recognizing Christ’s bold assertion of his authority allows us to dispense with any nonsense that Jesus was merely a great moral teacher.
- Jesus insisted on a radical internalization of biblical principles. Whereas the scribes focused on behaviors, Jesus focused on the heart: (Matthew 12:33-37/Tree and Its Fruit, Overflow of Heart, 19:16-22/Rich Young Ruler).
- Jesus applied truth in fresh ways that made sense in contrast with the arbitrary standards of the scribes. One example would be the matter of healing on the Sabbath and the Pharisees failure to give priority to the weightier matter of mercy (Matt 12:1-14). It’s like NFL rules where they are so caught up in defining a “catch” that it no longer describes a catch. Jesus said “I am the rule” – – not the NFL and I tell you the heart of the matter.
The emphasis on Jesus’s authority continues to the end of the Gospel. In Matthew 8 Jesus authority is referenced in both his exchange with the centurion and his rebuke of the storm. Even the wind and the waves obeyed him (Matt 8:27)!
In Matthew 9:8, the crowds are amazed that such authority was given to men.
By Matthew 10:1, Christ begins to share authority with the disciples.
Matthew argues for the authority of Christ by emphasizing the phrase “something greater.”
In Matthew 12:3-4, Matthew implicitly says that Christ is greater than David.
In Matthew 12:5-6, Matthew says that Christ is greater than the Temple.
In Matthew 12:42, Matthew says that something greater than Jonah is here.
In Matthew 12:43, Matthew says that something greater than Solomon is here.
Matthew 21:23 demonstrates that the issue of authority continues to be central in the Gospel of Matthew:
And when he entered the temple, the chief priests and the elders of the people came up to him as he was teaching, and said, “By what authority are you doing these things, and who gave you this authority?’”
Finally, Matthew concludes his gospel with Jesus’s assuring his disciples that all authority has been given to him and that he charges them to go into all the world and make disciples (Matthew 28:18-20).
See William Barclay’s chapter on the Authority of Jesus. I have not yet interacted with it extensively.
One of the challenges are day is that Christians too easily accept the authoritative presuppositions of the academy without evaluating them. We need to be unapologetic in saying that we accept Christ’s authoritative Word. For more on this subject, see Alvin Plantinga’s essay, Advice to Christian Philosophers. That essay concludes:
Christian philosophers must be wary about assimilating or accepting presently popular philosophical ideas and procedures; for many of these have roots that are deeply anti-Christian. And finally the Christian philosophical community has a right to its own perspectives; it is under no obligation first to show that this perspective is plausible with respect to what is taken for granted by all philosopher, or most philosophers, or the leading philosophers of our day. . . In sum, we who are Christians and propose to be philosophers must not rest content with being philosophers who happen, incidentally, to be Christians; we must strive to be Christian philosophers. We must therefore pursue our projects with integrity, independence, and Christian boldness.
 A common word, “ἐξουσία/authority” is found 102 times in the Greek New Testament.
 The word for astonished is “ἐκπλήσσομαι/ekplēssōmai”: “to be so amazed as to be practically overwhelmed” (Louw and Nida). It is found thirteen times in the Greek New Testament (Matt 7:28, 13:54, 19:25, 22:33; Mark 1:22, 6:2, 7:37, 10:26, 11:18, Luke 2:48, 4:32, 9:43; Acts 13:12).
 R.T. France, Matthew: Evangelist and Teacher (Grand Rapids: Zondervan, 1989), 168.
 See “Fulfill” on page 5.
 France, Matthew: Evangelist and Teacher, 187.
 Ibid., 18; W. D. Davies and Dale C. Allison, A Critical and Exegetical Commentary on the Gospel according to Saint Matthew: In Three Volumes, International Critical Commentary on the Holy Scriptures of the Old and New Testaments (Edinburgh: T. & T. Clark, 1988), 23–93.
 Regarding the beginning of the sermon, Bonhoeffer made an incredible observation in a footnote – that the warrant for his exposition is the phrase, “he opened his mouth.” Bonhoeffer wrote, “Even in the early Church this point was emphasized. Before Jesus speaks there is a pause – – all is silent for a moment or two.” Dietrich Bonhoeffer, The Cost of Discipleship, ed. Irmgard Booth (New York: Macmillan, 1963), 118, fn 1 .
 John R.W. Stott, The Message on the Sermon on the Mount (Matthew 5-7): Christian Counter Culture, ed. John R.W. Stott, The Bible Speaks Today (Leicester, England: Inter-Varsity Press, 1978), 212–215.
 Occurrences of ἐξουσία/exousia in Matthew are found in 7:28, 8:9, 9:6, 9:8, 10:1, 21:23, 21:24, 21:27, 28:18.
 France, Matthew: Evangelist and Teacher, 189.
 William Barclay, By What Authority? (Valley Forge: Judson Press, 1974), 78–110.
 Alvin Plantinga, “Advice to Christian Philosophers (With a Special Preface for Christian Thinkers From Different Disciplines),” n.d., https://www.calvin.edu/academic/philosophy/virtual_library/articles/plantinga_alvin/advice_to_christian_philosophers.pdf.