Both the background and the exact meaning of the expression times of spiritual strength are difficult to define. The word translated spiritual strength occurs only here in the New Testament and in the Septuagint (Exodus 8.15). Its meaning is given as “breathing space, relaxation, relief.” This expression does not appear in rabbinic literature, and as it stands is evidently not a Semitic idiom. However, most commentaries believe the phrase to mean those periods of refreshment during which God strengthens the human spirit.

In a number of languages times do not come. Rather, one can have “it will happen that” or as in this context, “so that you will have a time of rest” or “so that you will rest in your spirits.”

A literal translation of “rest” can be badly misunderstood. Obviously this passage does not refer to physical rest but to “rest for your spirits.” It is for that reason that an expression such as spiritual strength may be translated as “rest for your spirits” or “recuperation for your spirits.”

Not only is it difficult to speak of “times coming” in some languages, but they certainly would not come from the Lord’s presence. This is semantically almost impossible in most languages. Obviously the agent of this “coming” is the Lord himself. Therefore in some languages the structure must be altered so as to read “so that the Lord will send to you a time of renewing for your spirits.”

Where it is necessary to make a distinction in the use of Lord when it refers to God or Jesus, it is certainly possible in verse 20a to employ “Lord God.”

The second purpose to be accomplished through the repentance and turning to God is God’s sending of Jesus. This may be made very clear in some languages by saying “Do this so that the Lord will send a time of renewal for your spirits and so that he will also send Jesus.” The introduction of “also” is simply a way of indicating that there is a dual purpose.

It is possible to understand Messiah either as a title in apposition with the proper name Jesus (Jesus, who is the Messiah) or as a part of a proper name, Jesus Christ. Most translations have the former.

He has already chosen for you in the Greek is also a positive construction; but again it is obvious that God is the intended subject of the passive voice. Although the verb translated has already chosen may in itself mean “to choose” or “to appoint” without the idea of “beforehand” or “ahead of time” connected with it (see 22.14; 26.16, the only other places where this verb occurs in the New Testament), both the context and the tense of the verb suggest that here the idea is that of “choosing beforehand.”

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 .