{Having his head covered} (kata kephal(8873) ech(936e)).
Literally, having a veil (kalumma understood) down from the
head (kephal(8873) ablative after kata as with kata in  Mr
5:13  Ac 27:14 ). It is not certain whether the Jews at this time
used the _tallith_, "a four-corned shawl having fringes
consisting of eight threads, each knotted five times" (Vincent)
as they did later. Virgil (_Aeneid_ iii., 545) says: "And our
heads are shrouded before the altar with a Phrygian vestment."
The Greeks (both men and women) remained bareheaded in public
prayer and this usage Paul commends for the men.