6 There was a man sent from God, whose name was John.
This is a reference to John the Baptist, who paved the way for Christ’s appearance. He fulfilled several Old Testament prophecies such as;
Malachi 3:1 ¶ Behold, I will send my messenger, and he shall prepare the way before me: and the Lord, whom ye seek, shall suddenly come to his temple, even the messenger of the covenant, whom ye delight in: behold, he shall come, saith the LORD of hosts.
Isaiah 40:3 ¶ 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.
…which verses are referenced later in this chapter and, similarly in Mark 1:2, 3;
Mark 1:2 As it is written in the prophets, Behold, I send my messenger before thy face, which shall prepare thy way before thee. 3 The voice of one crying in the wilderness, Prepare ye the way of the Lord, make his paths straight.
John the Baptist came as a type of Elijah the Old Testament prophet, with his spirit and power, prophesied before his birth;
Luke 1:17 And he shall go before him in the spirit and power of Elias, to turn the hearts of the fathers to the children, and the disobedient to the wisdom of the just; to make ready a people prepared for the Lord.
…and revealed after his death by Christ Himself;
Matthew 17:10 And his disciples asked him, saying, Why then say the scribes that Elias must first come? 11 And Jesus answered and said unto them, Elias truly shall first come, and restore all things. 12 But I say unto you, That Elias is come already, and they knew him not, but have done unto him whatsoever they listed. Likewise shall also the Son of man suffer of them. 13 Then the disciples understood that he spake unto them of John the Baptist.
Mark 9:11 And they asked him, saying, Why say the scribes that Elias must first come? 12 And he answered and told them, Elias verily cometh first, and restoreth all things; and how it is written of the Son of man, that he must suffer many things, and be set at nought. 13 But I say unto you, That Elias is indeed come, and they have done unto him whatsoever they listed, as it is written of him.
Elias, or Elijah, did not perish like other men but was taken to heaven without dying.
2Kings 2:11 And it came to pass, as they still went on, and talked, that, behold, there appeared a chariot of fire, and horses of fire, and parted them both asunder; and Elijah went up by a whirlwind into heaven.
However, coming in the spirit and power of Elijah, based on the definitions of power and spirit in the Bible, does not necessarily include John being possessed by Elijah and certainly doesn’t refer to reincarnation as Elijah didn’t die but was carried up bodily into heaven in a type of the rapture of the believing Jews in Revelation 11.
The definition of spirit can be an attitude, a demeanor, and character as Caleb having, “another spirit.”
Numbers 14:24 But my servant Caleb, because he had another spirit with him, and hath followed me fully, him will I bring into the land whereinto he went; and his seed shall possess it.
Power can be ability as in Acts 1:8, speaking in authority as in Acts 4:33, and being filled with faith as in Acts 6:8, among other things.
John the Baptist did not have the spirit and power to call down fire on those who wanted him dead as in 2Kings, chapter 1, nor was he called to confront pagan prophets and have them killed as in 1Kings 18. He came to pave the way for Christ, to rebuke the hypocrites, and call the people to repentance and he did it forcefully and in opposition to not only religious authority but secular authority.
7 The same came for a witness, to bear witness of the Light, that all men through him might believe.
John the Baptist, like the Holy Ghost through the Spirit, pointed toward Christ that all men should believe in Christ and be saved. It is not God’s directive will that any man or woman should perish and go to Hell.
Matthew 18:10 Take heed that ye despise not one of these little ones; for I say unto you, That in heaven their angels do always behold the face of my Father which is in heaven. 11 For the Son of man is come to save that which was lost. 12 How think ye? if a man have an hundred sheep, and one of them be gone astray, doth he not leave the ninety and nine, and goeth into the mountains, and seeketh that which is gone astray? 13 And if so be that he find it, verily I say unto you, he rejoiceth more of that sheep, than of the ninety and nine which went not astray. 14 Even so it is not the will of your Father which is in heaven, that one of these little ones should perish.
1Timothy 2:1 ¶ I exhort therefore, that, first of all, supplications, prayers, intercessions, and giving of thanks, be made for all men; 2 For kings, and for all that are in authority; that we may lead a quiet and peaceable life in all godliness and honesty. 3 For this is good and acceptable in the sight of God our Saviour; 4 Who will have all men to be saved, and to come unto the knowledge of the truth.
2Peter 3:9 The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
So, Calvinists are wrong, in the assumption that God created certain people for the sole purpose of destroying them in eternity. But, those opposed to Calvinism often take free will to an extreme degree. You have the choice of whom you will follow and you make that choice, even as a believer, a dozen times a day with each decision of moral weight. But, you have no control over the outcome of your decision, only God does. If you follow your flesh sin will take you, as preachers say, farther than you want to go, make you stay longer than you want to stay, and make you pay more than you want to pay.
If you choose to follow God you may find yourself being led, like Moses, to things you never even imagined. Just measure all things that you think God has laid on your heart against the clear words of the Bible, “rightly dividing,” the word.
But, back to the verse, John the Baptist came to preach Christ, and he did.