Ymni_isodion_ths_theotoku_me_thn_tessarakontame...

: Many parishes perform a Divine Liturgy every day for 40 days leading up to Christmas (Nov 15 – Dec 25). The hymns of the "Isodia" are prominent during the first week of this journey.

: The Entrance of the Virgin Mary into the Temple. This is when the musical tone of the services shifts toward Christmas. ymni_isodion_ths_theotoku_me_thn_tessarakontame...

The phrase refers to the Hymns of the Entrance of the Theotokos (Isodia tes Theotokou) combined with the Tessarakontameron (the 40-day Christmas Lent period or "Sarantaleitourgo") in the Greek Orthodox tradition. : Many parishes perform a Divine Liturgy every

If you are looking for a specific or PDF booklet with this exact filename for a church choir, these are often found on Greek digital archives like Psaltologion or Analogion. This is when the musical tone of the

: Starting on November 21, the choir or chanter transitions from the standard hymns to the beautiful Christmas melodies during the Orthros (Matins) service.

The "put together guide" for this specific combination of the feast and the 40-day period typically involves:

: Incorporating the daily commemoration of saints alongside the pre-feast hymns of the Nativity.