You are looking at outward appearances. If anyone is confident that he belongs to Christ, he should remind himself that we belong to Christ just as much as he does.
Textus Receptus (TR) - 2 Corinthians 10:7 >Τὰ κατὰ πρόσωπον βλέπετε; Εἴ τις πέποιθεν ἑαυτῷ Χριστοῦ εἶναι, τοῦτο λογιζέσθω πάλιν ἀφ᾿ ἑαυτοῦ, ὅτι καθὼς αὐτὸς Χριστοῦ, οὕτω καὶ ἡμεῖς Χριστοῦ.