John Wesley on John 8:19

Then said they to him, Where is thy Father? Jesus answered - Showing the perverseness of their question; and teaching that they ought first to know the Son, if they would know the Father. Where the Father is - he shows, John 8:23. Meantime he plainly intimates that the Father and he were distinct persons, as they were two witnesses; and yet one in essence, as the knowledge of him includes the knowledge of the Father.