Birkenhead.
"[Greek: Pistis]," _unde deriv._ (Vol. ix., p. 324.).--The perfect
impossibility of deriving this word from [Greek: Histêmi] is at once
evident, on the following grounds: 1. To obtain the letter [pi], recourse
is had to the compound form [Greek: ephistamai]; but where have we a
similar instance, in any derived word, of the [epsilon] in [Greek: epi]
being thus absorbed, and the [pi] taken to commence a fresh word? 2.
Allowing such an extraordinary process, what possible meaning of [Greek:
ephistamai] can be adduced in the slightest degree corresponding to the
established interpretation of [Greek: pistis]?
Throwing aside the termination [Greek: -is], we obtain the letters [Greek:
pist-], which a very slight knowledge of etymology enables us to trace back
to [Greek: peithô]; for the stem of this verb is [Greek: PITH] (cf. Aor. 2.
[Greek: epithon]), and the formation of the adjective [Greek: pistos] from
[Greek: pe-peist-ai] is clearly analogous to that of the word in question,
the long syllable and diphthong [Greek: ei] being altered into the short
and single letter [Greek: i], to which many similar instances may be
adduced.
[Phi].
There is no doubt as to the derivation of [Greek: pistis] from [Greek:
peithô]. Compare [Greek: knêstis] from [Greek: knaô] or [Greek: knêthô],
[Greek: pristis] or [Greek: prêstis] from [Greek: prêthô], [Greek: pustis]
from [Greek: punthanomai]. Verbs of this form introduce the [Greek: s] into
the future and other inflected tenses, as [Greek: peisô], [Greek:
peusomai].