{A certain man} (	is).  Mt 8:19  calls him "a scribe."  Lu
9:57-60  Mt 8:19-22 , but not in Mark and so from Q or the Logia.
{Wherever you go} (hopou ean aperch(8869)) is the present middle
subjunctive with the indefinite relative adverb ean, common
Greek idiom. See on Matthew for "holes," "nests," "Son of man."
The idiom "where to lay his head" (pou t(886e) kephal(886e) klin(8869)) is
the same in both, the deliberative subjunctive retained in the
indirect question. "Jesus knows the measure of the scribe's
enthusiasm" (Plummer). The wandering life of Jesus explains this
statement.