The next day implies that on the very day that Cornelius had the vision he sent the men to Joppa, and they arrived there the next day. About noon (literally “about the sixth hour”) was no special time of prayer for Jews; and it is unnecessary to speculate, as some have done, whether this was a late morning prayer or an early afternoon prayer.

The Jewish house had a flat roof, which was reached by a stairway from outside. In areas of the world in which houses do not ordinarily have flat roofs, it may be necessary to add some marginal note or to place in the text itself the phrase “flat roof.” Without some supplementary information the implication of Peter going onto the roof might appear rather ludicrous or meaningless.

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 .