John 7:17

If any man will do his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself.

If any man will do, [ thelee (G2309 ), or better, 'is minded to do'] his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself - whether it be from above or from beneath, whether it be divine or an imposture of mine own. A principle of immense importance; showing, on the one hand, that singleness of desire to please God is the grand inlet to light on all questions vitally affecting one's eternal interest, and, on the other, that the want of this, whether perceived or not, is the chief cause of infidelity amidst the light of revealed religion.