John 14:16-18, 26

I will ask the Father, and he will give you another Helper to be with you forever— the Spirit of truth. The world cannot accept him, because it does not see him or know him. But you know him, because he lives with you and he will be in you. “I will not leave you all alone like orphans; I will come back to you.

But the Helper will teach you everything and will cause you to remember all that I told you. This Helper is the Holy Spirit whom the Father will send in my name.