To number or compare ourselves (enkrinai h sunkrinai). Paronomasia here, play on the two words. Enkrinai is first aorist active infinitive of old verb, but here only in N.T., to judge among, to judge one as worthy to be numbered among as here. The second verb sunkrinai (first aorist active infinitive of sunkrinw, old verb, in N.T. only here and 1 Corinthians 2:13 ) originally meant to combine as in 1 Corinthians 2:13 (which see), but here it has the sense of "compare" not found in the old Greek. The papyri use it to mean to decide. Plummer suggests "to pair and compare" for the play on the words here. Measuring themselves by themselves (en eautoi eautou metrounte). Or "in themselves." Keenest sarcasm. Setting themselves up as the standards of orthodoxy these Judaizers always measure up to the standard while Paul falls short. Comparing themselves with themselves (sunkrinonte eautou eautoi). Associate instrumental case eautoi after sunkrinonte (verb just explained). Paul is not keen to fall into the trap set for him. Are without understanding (ou suniasin). The regular form for present active indicative third plural of sunihmi, to comprehend, to grasp. Some MSS. have the late form suniousin (omega form suniw). It is a hard thing to see, but it is true. These men do not see their own picture so obvious to others ( Ephesians 5:17 ; 1 Timothy 1:7 ). Cf. Mark 8:17 .