3:1

the hour of prayer: Prayers were apparently offered at the temple in conjunction with the morning and evening sacrifices. (Ex 29:38-42; 30:7, 8) Luke connects “the hour of offering incense” with the time when “the people were praying.” (Lu 1:10) In providing details about the daily sacrifices, Jehovah commanded King David to organize the priests and the Levites to honor, thank, and praise Him, which doubtless included prayer. (1Ch 16:4; 23:30; 2Ch 29:25, 26) Incense and prayers were therefore closely related. (Ps 141:2; Re 5:8; 8:3, 4) At the hour of prayer, people typically assembled in the temple courtyards. Some likely came to be purified by the priests that day, while many others would have come to share in the prayers and worship in general. (Lu 2:22-38) Rabbinic tradition says that the priests determined by lot which one of them who had not previously presented incense on the golden altar should have this once-in-a-lifetime honor. With all the priests and Levites gathered, the chosen priest would solemnly enter the Holy while the priests and the people in the courtyards were praying. As the pleasing aroma of incense ascended, the people continued to pray in deep silence for about half an hour. (Lu 1:9, 10) “The hour of prayer” was then brought to a joyful finale that included a blessing of the people (Nu 6:22-27) and a chorus of Levites singing the psalm designated for that day of the week.

the ninth hour: That is, about 3:00 p.m.​—See study note on Ac 2:15.