Why is the teaching that Christ is in us believable to believers?
The teaching that Christ dwells in believers is believable because it is practical and experiential: those who love and know the Word recognize it has happened. Scripture confirms it, asking, 'Don't you know that you are the temple of God, and that the Spirit of God dwells in you?'
Les explains that the world knows nothing of this and might think he is a kook, but for those who love and know the Word, it is as plain as day. He says it is so believable because it is practical and experiential—believers know it has happened. He points to 1 Corinthians 3:16, where Scripture expects believers to know they are the temple or dwelling place of God and that the Spirit of God dwells in them. Since Christ is bodily at the Father's right hand and cannot leave that bodily, when we speak of Christ being in us, it must be in the third person of the Trinity, the Holy Spirit. Les also emphasizes that when Scripture repeats something in short order, it is emphasizing and making a point.