John 7:18

He that speaketh of himself
. What he himself has devised, and is a scheme of his own; for which he has no divine warrant and commission:

seeketh his own glory;
honour and applause from men; as did the Scribes and Pharisees, who taught for doctrines the commandments of men, the traditions of the elders, their own glosses upon the law, and their own decisions and determinations: and as did the false teachers, who had nothing else in view but themselves, their worldly interest, or vain glory; these suited their doctrines to the minds and lusts of men, in order to gain their point:

but he that seeketh his glory that sent him;
that gave him in commission what he should say and speak, and his only; as did Christ, and so his apostles after him:

the same is true, and no unrighteousness is in him;
he is an upright and faithful man, and what he says is truth; he brings true doctrine along with him, and there is no fraud or imposture in him; nor any insincerity "in his heart", as the Syriac and Persic versions render it; nor any dishonesty in his conduct; he is no cheat or deceiver; was he, he would seek his own glory and interest; but as he appears to be a man of no design, his doctrine is to be depended on and received; and such was Christ.