{When once} (aph' hou an). Possibly to be connected
without break with the preceding verse (so Westcott and Hort),
though Bruce argues for two parables here, the former (verse
 24 ) about being in earnest, while this one (verses  25-30 )
about not being too late. The two points are here undoubtedly. It
is an awkward construction, aph' hou = apo toutou hote with
an and the aorist subjunctive (egerth(8869) and apokleis(8869)).
See Robertson, _Grammar_, p. 978. {Hath shut to} (apokleis(8869)),
first aorist active subjunctive of apoklei(935c), old verb, but only
here in the N.T. Note effective aorist tense and perfective use
of apo, slammed the door fast. {And ye begin} (kai arx(8873)the).
First aorist middle subjunctive of archomai with aph' hou an
like egerth(8869) and apokleis(8869). {To stand} (hestanai). Second
perfect active infinitive of hist(886d)i, intransitive tense {and
to knock} (kai krouein). Present active infinitive, to keep on
knocking. {Open to us} (anoixon h(886d)in). First aorist active
imperative, at once and urgent. {He shall say} (erei). Future
active of eipon (defective verb). This is probably the apodosis
of the aph' hou clause.