We know that we live in Him, and He in us, because He has given us His Spirit.
Now we have received not the spirit of the world, but the Spirit which is of God, so that we might know the things that are freely given to us by God.
What? Do you not know that your body is the temple of the Holy Spirit, who is in you, whom you have received from God, and that you are not your own?
By this we know that we know Him, if we keep His commandments.
But whoever keeps His word truly has the love of God perfected in him. By this we know we are in Him.
Now the one who keeps His commandments remains in Him, and He in him. And by this we know that He remains in us, through the Spirit whom He has given us.