Where was the Church of SS John and Phocas in Constantinople?

Question

There's a brief line in Marcus Rautman's book, "Daily Life in the Byzantine Empire", in a passage on independent scribes. It refers to a "Theodore" who lived near John-and-Phocas in Constantinople.

The only other reference I can find is in "Bibles of the Christian East" by Georgri Parpulov where this is clarified as the Church of SS. John and Phocas.

Parpulov cites the following source at the end of his comment: Concilium universale Constantinopolitanum tertium, ed. R. Riediger, 2 vols. (Berlin: De Gruyter, 1990–2), vol. ii, pp. 652–3.

Can anyone shed any light on this church and its likely location? I haven't been able to find any reference to it anywhere else.

Answer 1

I found a reference of a shrine, by the sea. It does not say the location, and it was not a church but probably a minor building.

Yet, this shrine could have been build before (in the same place) of the nowadays Rum Orthodox Ayios Fokas Church (saint Phocas Church), which albeit being placed quite north in the Galatha, it is placed right by the sea.

This makes sense, since building a shrine out of the walls was a good option, instead of building an entire church.

Saint John is difficult to pin here, since there are many Saint Johns.