Question
We have daily readings from the Epistles and the Gospels, is there a list
of Orthodox or ‘approved’ daily readings for the Old Testament?
We have OT readings at vespers, but are they part of a greater cycle of OT readings?
Answer
For Great Feasts in which a Litiya is prescribed to be celebrated between
Vespers and Matins, one would find prescribed Old Testament readings in the
Festal Menaion.
For Lesser Feasts in which a Litiya is prescribed [such as the Beheading of
St. John the Baptist], one would find prescribed Old Testament readings in the
Monthly Menaion.
For Old Testament readings for the Liturgy of the Presanctified Gifts on
Wednesdays and Fridays of Great Lent and the first three days of Great Week,
one would consult the Lenten Triodion. These are generally also published on
the popular wall calendars most parishes distributed, but they are not always
complete.
For Old Testament readings for Vesper services during the Paschal season which
call for such readings, one should consult the Pentecostarion. There are also
Old Testament readings prescribed for a number of other services [such as the
Royal Hours on the Eve of the Nativity, on Great and Holy Friday, etc.], and
these would be found in the appropriate service books which cover those cycles
[such as the Festal Menaion and the Triodion respectively in the case of the
examples above].
Source: https://oca.org/questions/scripture/old-testament-readings
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