Scripture Union taught me the discipline of daily Bible reading..."John Stott,
Scripture taken from the Holy Bible, NEW INTERNATIONAL VERSION. Copyright © 1973, 1978, 1984 International Bible Society. All rights reserved throughout the world. Used by permission of International Bible Society.
I once was in a study group when this question was asked, "How can we distinguish between the Holy Spirit in us and Christ in us?" The answer the leader gave was, "We cannot distinguish between the two experiences. For the Holy Spirit is Christ in us. The Holy Spirit is Jesus Christ who came back to his disciples as an abiding presence."
Jesus told his disciples he would be with them until the end of the age (Matt. 28:20). The Holy Spirit indwelling the believer is the fulfillment of that promise. Through the Holy Spirit, Christ is personally present and active with his people.
In John 14, Jesus startled his disciples by telling them that after being with them for three years he was soon going to leave them (2). They would not be orphans (18), however, because he would still be with them. This is stated by the use of three Greek prepositions: "with you" (meta, v. 16) meaning to keep company with, "with you" (para, v. 17) meaning parallel to, and "in you" (en, v. 17) meaning in you like an embryo in an egg (17). What wonderful intimacy! This would be fulfilled for the disciples at Pentecost (Acts 2) and for the believer at conversion.
For us, the Holy Spirit indwells our heart by faith (Eph. 3:16,17) and does his transforming work there. He not only shows Christ to us but forms Christ in us. He does this by working deep in our personalities, revealing sin and cultivating goodness within us. We are also required to be part of the process. We must consistently "crucify the sinful nature with its passions and desires" (Gal. 5:24) and yet yield to the Holy Spirit and "keep in step with the Spirit" (Gal. 5:25).