-FAITH: The essence of the disciple’s lack of faith is partly revealed in this section before and after this event in their reaction to the revelation of the cross. They had no realization of the redemptive work of Christ. They were plagued with a wanting gospel understanding. They lacked the active spiritual ingredients for deliverance, as the cross is the only ultimate ground for our alleviation of judgement and suffering. It is never a physical limitation that stands between the believer and a robust testimony of the glory of God, but a spiritual limitation – here their faithless heart condition was the saboteur of works. There is no faith void of evident works and there are no works independent of faith.

-LEAST OF THESE: Note this healing of a child in light of Mat 18’s admonition…to deceive, corrupt, neglect, or spiritually blind a child renders one in league with this demon…no less disturbing is the spiritual neglect of a little one… This exchange situated here in the record serves in part to further illustrate the severity of the opening theme of Discourse #4 (our Christian duty to children and the childlike)

-MUSTARD SEED:
Cross ref Mat 13:31-32 for exegetical application of the mustard seed analogy. *Mustard seeds produced the largest of all herbs. In Mat 13, the seed is the kingdom of God. As such it is not diminutive in any sense as to its essence, the size refers to its sovereign/prescribed/decreed process of growth. In Mat 17, the connection is most clearly drawn when we consider faith as an intrinsic establishment of the Kingdom of God in each follower of Christ by His sovereign hand such that it begins to flourish and bear the fruit of experience, testimony, the evident indwelling of the Spirit, etc. This reality was as yet outstanding for this particular group of disciples and evidently so by their impotence manifest in this confrontation with spiritual forces. Reference Acts 19:13-17 …here itinerant Jewish exorcists invoke the name of Christ without the faith of Christ in their hearts to ill effect and devastating consequence… meanwhile the contrasting testimony of the exclusive authority and power vested in the name of Christ compelled those looking on to fear The Lord and renounce their idols!

-MOUNTAIN: Consider the kingdom context of mustard seed alongside the weight of interpretation of ‘mountain’ in light of Biblical kingdom references (Christ could well be invoking the landscape behind him as an object lesson i.e. the mountain he has just descended) Every metaphorical mountain must bow before Christ!
…Mat 21:21-22 similar declaration.
…Mountains frequently are referenced in scripture to (define boundaries geopolitical, delineate ethnic division, identify separation of lands, denote formidable positions of power, reference high places of worship, symbolize kingdoms )
…Jer 51:24 – 25 -64 Babylon is characterized as a destroying mountain that will be destroyed
…Couple this with the crescendo of eschatological history in Dan 2:34-35 a stone cut by no human hand fills the earth as a mountain eclipsing/ destroying every imposter kingdom (mountain).
…Also Isaiah 14:13 & context contains reference to a mount of assembly which recalled, in judgement proclamation, the Babylonian myth of the seat of the gods (Easton’s).
…Isaiah 54:10,12 Prophecy of Israel’s restoration and covenant hope incorporates imagery of mountains to underscore the surety and transcendent duration of the promises of restoration of God’s covenant people and also the disarming of all once formidable obstacles which now surrender to the glory of God!
…Ezekiel 6:3-7 Mountains pictured as judgement-worthy locations as high places were preferred sites for altars to false gods, pagan worship, blasphemous temple mounts.

-TAXES: incident involving a tax prescribed in Ex 30:11-16. This tax, given it’s historically instituted purpose under Moses (15-16 “…the Lord’s offering to make atonement for your lives”), becomes contextually important here in Matthew’s gospel as this immediately follows Christ’s own proclamation that He would soon offer Himself as an atonement offering. (Mt 17:22-23)
…Jesus distinguishes himself from the subjugation relationship that a levied tax implies using the analogy of dynastic sonship vs. mere citizenship (implicit Son of David reference) and instructs Peter to pay them for other reasons.

-SUFFERING SON OF MAN: Sproul notes an apparent historical blind spot with reference to the mystery of the identity of the Messiah, Suffering Servant, & Son of Man (like rabbinic confusion as to the identity of Elijah to come) it had not occurred to those unenlightened by the Spirit that these three prophetic concepts would be embodied in one God/man (Jesus), hence the befuddlement following Jesus revelation of His passion, death, and resurrection. (Mat 17:22-23).