{Therefore} (men oun). Because of the preceding situation.
{Was kept} (et(8872)eito). Imperfect passive, continuously guarded,
waiting for the feast to be over. {But prayer was made earnestly}
(proseuch(8820)de (886e) ekten(9373) ginomen(885c)). Probably de here is not
adversative (but), merely parallel (and) as Page argues. It was a
crisis for the Jerusalem church. James had been slain and Peter
was to be the next victim. Hence "earnestly" (late adverb from
ekten(8873), strained, from ektein(935c), to stretch. In the N.T. only
here,  Lu 22:44  1Pe 1:22 ) prayer was {going up} (ginomen(885c),
present middle participle, periphrastic imperfect with (886e)). It
looked like a desperate case for Peter. Hence the disciples
prayed the more earnestly.