273. An Optional Mincha

Tefillah u’Birkas Kohanim 3:3

There are people who recite mincha twice – once at the time of mincha gedolah and again at the time of mincha ketana – considering one of these to serve as a voluntary prayer service. Some Geonim said that it is only proper to recite the optional prayer at mincha gedolah. This makes sense, as that time corresponds to a time when the afternoon sacrifice was offered only infrequently. If one recites mincha intending to fulfill his obligation at the time of mincha gedolah, he should only recite an optional service at mincha ketana.

Tefillah u’Birkas Kohanim 3:4

We have established that the time of mincha gedolah is from six and a half hours until nine and a half hours of the day, and that mincha ketana lasts from nine and a half hours until there are one and a quarter hours left in the day. However, mincha may be recited until sunset.