Read John 14:15-23
When I am raised to life again, you will know that I am in my Father, and you are in me, and I am in you. – John 14:20 (NLT)
When Christ is in us, we come to know God experientially, from seeing Him show up in our lives on a regular basis. God is then able to reveal Himself to others through us, through our witness. because we can testify to what He has done, not just 2000 years ago when He won our salvation, but right now in our lives.