"A voice is calling, “Clear the way for the Lord in the wilderness; Make smooth in the desert a highway for our God. (Isaiah 40:3)
"Behold, I am going to send My messenger, and he will clear the way before Me. And the Lord, whom you seek, will suddenly come to His temple; and the messenger of the covenant, in whom you delight, behold, He is coming,” says the Lord of hosts." (Malachi 3:1)
These passages are obviously speaking of God the Father. But the New Testament applies both of these messages to Jesus Christ, as well.
It is abundantly clear that these texts, when connected, are saying that John the Baptist is the prophesied forerunner to prepare the way for the coming of the Lord God. Jesus is God in the flesh. God the Son is the promised Jewish Messiah.