John Calvin on John 14:18

18. I will not have you orphans. This passage shows what men are, and what they can do, when they have been deprived of the protection of the Spirit. They are orphans, exposed to every kind of fraud and injustice, incapable of governing themselves, and, in short, unable of themselves to do any thing. The only remedy for so great a defect is, if Christ govern us by his Spirit, which he promises that he will do. First then, the disciples are reminded of their weakness, that, distrusting themselves, they may rely on nothing else than the protection of Christ; and, secondly, having promised a remedy, he gives them good encouragement; for he declares that he will never leave them When he says, I will come to you, he shows in what manner he dwells in his people, and in what manner he fills all things. It is, by the power of his Spirit; and hence it is evident, that the grace of the Spirit is a striking proof of his Divinity.

John 14:19-20

19. Yet a little while, and the world shall see me no more; but you see me: because I live, you also shall live. 20. At that day you shall know that I am in the Father, and you in me, and I in you.