This was prophecy spoken of by Zacharias concerning the ministry of his son, John Baptist.
Luk 1:67-80
67 And his father Zacharias was filled with the Holy Ghost, and prophesied, saying,
68 Blessed be the Lord God of Israel; for he hath visited and redeemed his people,
69 And hath raised up an horn of salvation for us in the house of his servant David;
70 As he spake by the mouth of his holy prophets, which have been since the world began:
71 That we should be saved from our enemies, and from the hand of all that hate us;
72 To perform the mercy promised to our fathers, and to remember his holy covenant;
73 The oath which he sware to our father Abraham,
74 That he would grant unto us, that we being delivered out of the hand of our enemies might serve him without fear,
75 In holiness and righteousness before him, all the days of our life.
76 And thou, child, shalt be called the prophet of the Highest: for thou shalt go before the face of the Lord to prepare his ways;
77 To give knowledge of salvation unto his people by the remission of their sins,
78 Through the tender mercy of our God; whereby the dayspring from on high hath visited us,
79 To give light to them that sit in darkness and in the shadow of death, to guide our feet into the way of peace.
80 And the child grew, and waxed strong in spirit, and was in the deserts till the day of his shewing unto Israel.
John Baptist was to go before the face of the Lord to prepare His ways ... John Baptist was the forerunner to Messiah.
John Baptist was to give knowledge of salvation ... it is Messiah Who gives salvation and remission of sins.
John Baptist pointed to the Dayspring from on high ... Messiah.
John Baptist taught God's Word ... it is God's word which gives light to them that sit in darkness and in the shadow of death, to guide our feet unto the way off peace.
John Baptist was faithful to his calling ...
Mathew 3:1-12
1 In those days came John the Baptist, preaching in the wilderness of Judaea,
2 And saying, Repent ye: for the kingdom of heaven is at hand.
3 For this is he that was spoken of by the prophet Esaias, saying, The voice of one crying in the wilderness, Prepare ye the way of the Lord, make his paths straight.
4 And the same John had his raiment of camel's hair, and a leathern girdle about his loins; and his meat was locusts and wild honey.
5 Then went out to him Jerusalem, and all Judaea, and all the region round about Jordan,
6 And were baptized of him in Jordan, confessing their sins.
7 But when he saw many of the Pharisees and Sadducees come to his baptism, he said unto them, O generation of vipers, who hath warned you to flee from the wrath to come?
8 Bring forth therefore fruits meet for repentance:
9 And think not to say within yourselves, We have Abraham to our father: for I say unto you, that God is able of these stones to raise up children unto Abraham.
10 And now also the axe is laid unto the root of the trees: therefore every tree which bringeth not forth good fruit is hewn down, and cast into the fire.
11 I indeed baptize you with water unto repentance: but he that cometh after me is mightier than I, whose shoes I am not worthy to bear: he shall baptize you with the Holy Ghost, and with fire:
12 Whose fan is in his hand, and he will throughly purge his floor, and gather his wheat into the garner; but he will burn up the chaff with unquenchable fire.
see also Luke chapter 3.
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