Luke 3:4
This was according to what is written in the book containing the words of Isaiah, the prophet [Isa. 40:3ff], "The voice of a man who speaks out in the desert [urging people] to make the road for the Lord ready [for Him to travel]; to make a straight pathway for Him [to walk on].
John 1:23
He replied, "I am the voice of a man who is calling out in the desert, [urging people to] 'Make the road for the Lord straight,' as Isaiah the prophet said, [Isa. 40:3]."
Matthew 3:3
For this is the man who was spoken of by Isaiah the prophet, who said, [Isa. 40:3], "[It is] the voice of a man who speaks out in the desert, [urging people to] make the road for the Lord ready [for Him to travel]; to make a straight pathway for Him [to walk on]."
Mark 1:3
He will be the voice of a man shouting out in the desert, [urging people] to make the road for the Lord ready [to travel on]; to make a straight pathway for him."
Luke 1:16-17
And he will influence many Israelites to turn to the Lord their God.
Luke 1:76-79
Yes, you [my] child [i.e., John], will be called the prophet of the Highest [i.e., God], for you will go ahead of the Lord's presence to prepare His ways.
John 1:7
He came to be a witness, so that he might testify concerning that Light, so that all people would believe [in Jesus] through him [i.e., through his testimony. See Acts 19:4].
John 1:26-36
So, John answered them, saying, "I am immersing people in water, but there is Someone among you whom you do not recognize.
John 3:28-36
You yourselves can testify that I said, 'I am not the Christ [i.e., God's specially chosen one] but [rather] that I was sent [by God] ahead of Him.'