There is also the possibility, mentioned by R. V. G. Tasker, that EIS
TO ONOMA... was a current Greek usage meaning that the thing acted upon
comes to belong to the person named (See Deissmann, _Bible Studies_, pp.
147, 197; and Moulton & Milligan,
s.v. ONOMA). In this case we would be baptized into belonging to the
Father, Son and Holy Spirit.
On the use of the singular ONOMA with more than one name, as in Mat.
28:19, let me mention Deissmann's citation of a possibly related
construction in a papyrus from Fayyum in the "reign of Antonius Pius" (?).
The phrase runs in Greek as follows: TA
U(PARCONT[A] EIS ONOMA DUEIN. Which translates to, "that (i.e. property
or means) which belongs to the name of the two."
David L. Moore