65 The word “people” is not in the Greek text, but is supplied to clarify that the following verbs (“heard,” “seen,” “have residing,” “do not believe”) are second person plural.
66 You people have never heard his voice nor seen his form at any time. Compare Deut 4:12. Also see Deut 5:24 ff., where the Israelites begged to hear the voice no longer—their request (ironically) has by this time been granted. How ironic this would be if the feast is Pentecost, where by the 1st century a.d. the giving of the law at Sinai was being celebrated.

In other versions

And the Father who sent me has himself borne witness about me. His voice you have never heard, his form you have never seen,

And the Father who sent me has himself testified concerning me. You have never heard his voice nor seen his form,

The Father who sent me has himself testified about me. You have not heard his voice at any time, and you haven’t seen his form.

And the Father who sent me has testified about me himself. You have never heard his voice or seen him face to face,

And the Father who sent me, that one has testified about me. You have neither heard his voice at any time nor seen his form.

And the Father himself, which hath sent me, hath borne witness of me. Ye have neither heard his voice at any time, nor seen his shape.

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