And Paul concluded must be rendered in some languages as “and Paul also said before they left.” Otherwise it might appear that this was Paul’s final judgment on the Jews after they had departed.

In this verse, as in 13.48 and 18.6, a proclamation of God’s message to the Gentiles is initiated by the refusal on the part of the Jews to hear it. You are to know is a very strong and solemn expression (see 2.14; 4.10; 13.38). The equivalent rendering of you are to know may be “you must know.” In some languages this can only be adequately reproduced as “I must tell you so that you will know.”

The phrase “the salvation of God” has been taken by the Good News Translation with the meaning God’s message of salvation (see also An American Translation*). From the context it is quite evident that Paul’s emphasis is on the message of salvation rather than on salvation itself, though in the final analysis these two ideas cannot be separated from one another. God’s message of salvation may be rendered as “the message about salvation that comes from God.” However, in such a phrase it must be perfectly clear that it is the message that comes from God, though theologically speaking, it is also the salvation which proceeds from God. To make this perfectly clear, one may translate “the message that God has proclaimed about his saving people.” In some languages, however, one cannot speak about “sending a message.” One can only “send a messenger” or “send a person to speak a message.” Therefore, in this clause one may translate: “those who announce what God has said about salvation have been sent to the Gentiles.”

In the statement they will listen, the they is emphatic.

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on The Acts of the Apostles. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .