The 4 hour August "Zazenkai" retreat will be on Saturday 8/4 and commences from 9 p.m. Japan time (currently New York 8am, Los Angeles 5am, London 1pm and Paris 2pm, Saturday) ... and continues for 4 hours as follows:
00:00 – 00:50 CEREMONY (HEART SUTRA in English ONLY / SANDOKAI) & ZAZEN
00:50 – 01:00 KINHIN
01:00 – 01:40 ZAZEN
01:40 – 01:50 KINHIN
01:50 – 02:30 ZAZEN & DHARMA TALK
02:30 – 02:40 KINHIN
02:40 – 03:20 ZAZEN
03:20 – 03:30 KINHIN
03:30 – 04:00 METTA CHANT & ZAZEN
04:00 – 04:10 FOUR VOWS, VERSE OF ATONEMENT & CLOSING COMMENTS
As you can see, there will be 5 periods of Zazen, each 40 minutes long, although several include time for chanting. In between each period of Zazen, there will be a 10 minute period for Kinhin walking (which will also serve for any needed bathroom breaks).
More information here
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