As may be gathered from the more literal rendering of Revised Standard Version (For this is he who), John is not actually mentioned by name in the Greek text. Good News Translation and Die Bibel im heutigen Deutsch mention the name explicitly for stylistic reasons. Actually, most translators will find that doing this will help their readers to follow the flow of the passage better. Another way may be “It was John that the prophet Isaiah was talking about.”
For does indicate that John’s ministry was a fulfillment of the prophecy of Isaiah. Good News Translation showed this relation with the expression “John was the man…,” without using the word “for.” Another way to do this may be “In fact, John was the person….”
There are languages which more naturally start this verse with “Isaiah.” But translators must make sure that the focus is still on John: “Isaiah the prophet had spoken about someone and said, ‘Someone is shouting … for him to travel.’ That person he spoke of was John.”
For comments on prophet, see 1.22.
The quotation of Isaiah 40.3, which Matthew has taken over from Mark (1.2-3), differs from the quotations in chapters 2 and 3 in that the “to be fulfilled” is lacking. At this point Matthew clearly adopts the Septuagint, in which the phrase in the wilderness is connected with crying (Good News Translation “shouting”) rather than with the imperative Prepare, as in Hebrew.
There is, however, one important distinction between the Septuagint text and the quotation in Matthew and Mark: in place of make his (the Messiah’s) paths straight, the Septuagint follows the meaning of the Hebrew: “make a straight path for our God to travel.” In other words, both the Hebrew and the Septuagint consider “the Lord” to refer to God, while Matthew interprets “the Lord” as referring to the expected Messiah.
Good News Translation has translated clearly the meaning of the ambiguous expression his paths by “path for him to travel.”
It is difficult in many languages to speak of a voice shouting. Instead translators may say “The voice of someone” or just “Someone.” Another possibility is to say “People hear the voice of someone shouting….”
Crying does not mean “weeping” here, but “shouting.”
The same word for wilderness is used here as in Matthew 3.1. Translators should use the same word in both verses so that the connection between them is clear.
Many languages must introduce what the voice said, with “He (or, That person) said” or “saying,” or even “He was saying.”
Prepare the way means “Get a road ready,” “Make a road,” or even “Cut a path.” Of course Isaiah is not speaking literally of a road but is actually speaking about providing the right circumstances so that the Lord can come. However, translators should keep the figure Isaiah used, if at all possible.
The way of the Lord is a road “for the Lord,” a road “on which the Lord can travel,” or “for him to travel on.”
The second command, to make his paths straight, has essentially the same meaning as the first one, as in “Make straight paths for him” or “Prepare straight paths for him (to travel on).”
Since it is understood that this path or road is for the Lord to travel on as he comes to us, some translators say something like “to travel on to us” or “to come to his people.”
Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .