{Came round about him} (ekukl(9373)an auton). Aorist active
indicative of kuklo(935c), old verb from kuklos (cycle, circle).
See  Ac 14:20  for the circle of disciples around Paul when
stoned. Evidently the hostile Jews cherished the memory of the
stinging rebuke given them by Jesus when here last, particularly
the allegory of the Good Shepherd ( 10:1-19 ), in which he drew
so sharply their own picture. {How long dost thou hold us in
suspense?} (he(9373) pote t(886e) psuch(886e) h(886d)(936e) aireis;). Literally,
"Until when dost thou lift up our soul?" But what do they mean by
this metaphor? Air(935c) is common enough to lift up the eyes ( Joh
11:41 ), the voice ( Lu 17:13 ), and in  Ps 25:1  86:4 
(Josephus, _Ant_. III. ii. 3) we have "to lift up the soul." We
are left to the context to judge the precise meaning. Clearly the
Jews mean to imply doubt and suspense. The next remark makes it
clear. {If thou art the Christ} (ei su ei ho Christos).
Condition of first class assumed to be true for the sake of
argument. {Tell us plainly} (eipon h(886d)in parr(8873)i(8369)). Conclusion
with eipon rather than the usual eipe as if first aorist
active imperative like luson. The point is in "plainly"
(parr(8873)i(8369)), adverb as in  7:13,26  which see. That is to say
"I am the Christ" in so many words. See  11:14  16:29  for the
same use of parr(8873)i(8369). The demand seemed fair enough on the
surface. They had made it before when here at the feast of
tabernacles ( 8:25 ). Jesus declined to use the word Christos
(Messiah) then as now because of the political bearing of the
word in their minds. The populace in Galilee had once tried to
make him king in opposition to Pilate ( Joh 6:14f. ). When Jesus
does confess on oath before Caiaphas that he is the Christ the
Son of God ( Mr 14:61f.  Mt 26:63f. ), the Sanhedrin instantly
vote him guilty of blasphemy and then bring him to Pilate with
the charge of claiming to be king as a rival to Caesar. Jesus
knew their minds too well to be caught now.