A.T. Robertson Commentary John 3:21

"But he that doeth the truth cometh to the light, that his works may be made manifest, that they have been wrought in God." — John 3:21 (ASV)

That doeth the truth (ο ποιων την αληθειαν). See 1 John 1:6 for this striking phrase.

Comes to the light (ερχετα προς το φως). Is drawn by the light, spiritual heliotropes, not driven from it.

That may be made manifest (ινα φανερωθη). Final ινα with first aorist passive subjunctive of φανεροω.

They have been wrought in God (εν θεω εστιν ειργασμενα). Periphrastic perfect passive indicative of εργαζομα. He does not claim that they are perfect, only that they have been wrought in the sphere of and in the power of God. Hence he wants the light turned on.