Ymni_isodion_ths_theotoku_me_thn_tessarakontame...

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

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. 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