Jesus in your heart by faith has slipped out of American Christianity. Mainly because only kids were told Jesus was in them. It is a Bible verse that Christ is in your heart by faith. Telling an American "by faith" is like saying its not happening for you. Simply understand that it is only Salvation faith that is required to have Jesus in your heart is what we all forgot. And that's what it used to be understood when children prayed to ask Jesus in their hearts. The profound thing is that Jesus really is there even if you are saved. We just are not told Why or what he does. People have no problem with the idea of regeneration and the Holy Spirit being in them. Especially Pentecostals who believe The Spirit is active in them. This is why it says, by Faith. Because there may be no work or sign that proves Jesus is even there. Some people take it figurative. That Jesus simply loves us is the interpretation. But that is not what it means. Jesus in your heart by faith, means that He is really there with Holy Spirit doing ministry. What ministry? That everything the Spirit ever said to you was spoken by Christ according to the Scripture which says the Spirit only speaks what He hears from Christ. It actually is that both are in you conversing. The classic THUS SAITH THE LORD (Jesus) is actually Christ and Spirit fulfilling that even though the Spirit is saying it as even in Old Testament, It is still Christ speaking through the Spirit.