There are nine Biblical Canticles that are chanted at Matins These form the basis of the Canon, a major component of Matins.
The nine Canticles are as follows:
Canticle One – The (First) Song of Moses (Exodus 15:1-19)
Canticle Two – The (Second) Song of Moses (Deuteronomy 32:1-43)
Canticle Three – The Prayer of Hannah (I Kings 2:1-10) KJV: 1+Samuel 2:1-10
Canticle Four – The Prayer of Habakkuk (Habakkuk 3:1-19)
Canticle Five – The Prayer of Isaiah (Isaiah 26:9-20)
Canticle Six – The Prayer of Jonah (Jonah 2:2-9)
Canticle Seven – The Prayer of the Three Holy Children (Daniel 3:26-56)
Canticle Eight – The Song of the Three Holy Children (Daniel 3:57-88)
Canticle Nine – The Song of the Theotokos (the Magnificat: Luke 1:46-55); the Song of Zacharias (the Benedictus Luke 1:68-79)
Originally, these Canticles were chanted in their entirety every day, with a short refrain inserted between each verse. Eventually, short verses (troparia) were composed to replace these refrains, a process traditionally inaugurated by Saint Andrew of Crete. Gradually over the centuries, the verses of the Biblical Canticles were omitted (except for the Magnificat) and only the composed troparia were read, linked to the original canticles by an Irmos. During Great Lent however, the original Biblical Canticles are still read.
Another Biblical Canticle, the The Song of Simeon (Luke 2:29-32), is either read or sung at Vespers.