Luke 1:76-80

Luke 1:76 (KJB)
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;

This part of the prophecy of Zacharias focuses on his son John. If you notice he calls him “child” instead of son because the ministry of John will be more important than the family relationship. John’s main function will be to prepare the hearts of the people for the coming of the Messiah. John will be the last prophet of the Old Testament. At this point he is still on the Old Testament side of the cross. (Mat 3:3 KJV) 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. It is taken from the prophecy of Isaiah in chapter 40. (Isa 40:3 KJV) The voice of him that crieth in the wilderness, Prepare ye the way of the LORD, make straight in the desert a highway for our God. His ministry was foretold 750 years before his birth.

Luke 1:77 (KJB)
To give knowledge of salvation unto his people by the remission of their sins,

His primary preaching focus will be to bring the knowledge of salvation to the people of Israel by way of remission of their sins. The remission is the forgiveness of their sins. John was only able to bring the knowledge of this because he did not have the ability to do the forgiving of the sins. The people of Israel had to know that they needed to be freed from their real enemy which was not Rome but was from their sin, which would cause them to be judged on the last day and be cast into hell. Forgiveness of sins would come through the Lord Jesus Christ. (Acts 5:31 KJV) Him hath God exalted with his right hand to be a Prince and a Saviour, for to give repentance to Israel, and forgiveness of sins.

Luke 1:78 (KJB)
Through the tender mercy of our God; whereby the dayspring from on high hath visited us,

Because of the tender heart of mercy which causes God to love the world, John would be able to accomplish his mission. This same mercy would cause the dayspring which is the dawn to visit the people of Israel. This is not speaking of just the beginning of a day but it is beginning of the day of the Lord prophesied back in Isaiah. (Isa 60:1 KJV) Arise, shine; for thy light is come, and the glory of the LORD is risen upon thee. Christ would bring the light of the Gospel into the sinful darkness of human life.

Luke 1:79 (KJB)
To give light to them that sit in darkness and in the shadow of death, to guide our feet into the way of peace.

Christ would be the one who would bring the light to all those that are the Elect. (1 John 2:8 KJV) Again, a new commandment I write unto you, which thing is true in him and in you: because the darkness is past, and the true light now shineth. Once Christ saves a person, the darkness will be a thing of the past. John will have the privilege of being the one who will introduce the Messiah. The peace that Christ will give will be the cessation of hostility between sinful man and a holy God. (Rom 5:1 KJV) Therefore being justified by faith, we have peace with God through our Lord Jesus Christ: The way will be open to the Father but only through Christ. He will not only guide us in peace, but will also guide us through this entire life. (Psa 48:14 KJV) For this God is our God for ever and ever: he will be our guide even unto death.

Luke 1:80 (KJB)
And the child grew, and waxed strong in spirit, and was in the deserts till the day of his showing unto Israel.

Probably because of the advanced age of Elisabeth and Zacharias, they passed from the scene. John had continued to grow physically and as he did he was becoming stronger in the power of the Holy Spirit. John then spent the remaining years before his sudden appearance in the deserts. It was a lonely and barren place which was inhabited by wild animals. It was probably the perfect training ground for John until the day he was to appear to the people of Israel. Just as Elijah had appeared suddenly in 1 Kings 17, John also made a very sudden and unannounced appearance when he started his ministry.