In particular, his musical settings of the eirmoi (unsurpassed both in quality and in quantity by his contemporaries) gave rise to a style of paraliturgical chant that came to be known as the kalophonic eirmological style, named for its beautiful melodic theses.
The eight-mode, two choir structure format employed by Bereketis in his notable setting of "O Theotokos and Virgin" was inspired by a similar composition ("More Honourable than the Cherubim") by Constantine of Aghialos, written several centuries earlier.