This was to fulfil what was spoken by the prophet: see comments on 1.22. Here the sentence may be “He did this to make come true what the prophet said would happen.” The form used here is exactly the same as in 8.17, except there the prophet is identified as Isaiah. In fact some Greek manuscripts even include “by Isaiah the prophet” here. As TC-GNT indicates, its inclusion is obviously the more difficult wording, since the passage actually comes from Psalm 78.2 rather than from Isaiah. On the other hand, it is also possible that Isaiah’s name was inserted because he is the most famous of the Old Testament prophets. In light of the conflicting and difficult evidence, the UBS Greek text committee decided in favor of omitting the prophet’s name. But they rate this a “C” decision, indicating a considerable degree of doubt regarding the wording of the text.

It may be good in some languages to introduce the citation with “he said” or some similar marker of direct discourse.

I will open my mouth in parables makes use of the Semitic idiom “to open one’s mouth,” which means “to speak.” Thus it can be rendered as “I will speak in parables” or “I will use parables when I speak (to them).”

Utter (so also New English Bible) originally meant “belch” but later developed the meaning “proclaim” or “tell” (Good News Translation). Most modern English translations evidently prefer utter; Jerusalem Bible has “expound” and New American Bible “announce.” In the present context the verb is obviously used as a parallel to the verb “speak” of the first sentence. Other possible renderings of utter are “explain to them” or “teach them about.” Die Bibel im heutigen Deutsch translates the entire quotation as “I will speak in parables, only in parables will I uncover what has been hidden since the creation of the world.”

What has been hidden since the foundation of the world may be translated “things which God has not let people know since he created the world” or “things which people have never known before.”

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 .