Question: "What is Christian mysticism?"
Answer: Christian mysticism is a difficult term to define. It is often thought of as the practice of the experiential knowledge of God. The term can also apply to the mystery of the Eucharist in Roman Catholicism as well as so-called hidden meanings of Scripture, such as in Gnosticism. The Bible does not have hidden meanings, nor do the elements of communion become Christ's literal body and blood. Although it is true that Christians experience God, Christian mysticism tends to elevate experiential knowledge and revel in the mysterious, focusing on mysticism for spiritual growth. Biblical Christianity focuses on knowing God through His Word (the Bible) and communion with the Holy Spirit through prayer. Mysticism tends to be an individual, subjective practice whereas biblical Christianity is both an individual relationship with God and one that is necessarily lived out in community. There is no such thing as a solo Christian. Not all of what could be considered "Christian mysticism" is wrong, but much of it is, and a focus on mysticism can certainly lead one into error.
Mysticism can be found in many religions. Often it involves asceticism of some type and seeks union with God. It is certainly right to want to draw close to God, but mystical union with God is different from the type of intimacy with God to which Christians are called. Mysticism tends to seek out the experience and is sometimes seen as secretive or elitist. Christians are aware of and engaged in spiritual realities (Ephesians 1:3; 6:10–19) and biblical Christianity involves spiritual experience, but intimacy with God is intended for all Christians and is not veiled by any sort of mysterious practice. Drawing near to God is nothing mysterious or elitist but involves things like regular prayer, studying God's Word, worshiping God, and fellowshipping with other believers. Our efforts pale in comparison to the work God Himself does in us. In fact, our efforts are more a response to His work than they are something that originates in us.
Christians do have what might be considered mystical experiences. When we accept Jesus as Savior, we are indwelled by the Holy Spirit. The Holy Spirit transforms us and enables us to live out God's calling. Often, filled with the Holy Spirit, a Christian will demonstrate great wisdom or faith or spiritual discernment. A Christian filled with the Holy Spirit will also demonstrate things like love, joy, peace, patience, kindness, gentleness, faithfulness, and self-control (Galatians 5:22–23). The Holy Spirit helps believers understand truth and live it out (1 Corinthians 2:13–16). This is not the result of mystical practices but a sign of the indwelling Holy Spirit at work. Second Corinthians 3:18 talks about the Holy Spirit's work in our lives: "And we all, who with unveiled faces contemplate the Lord's glory, are being transformed into his image with ever-increasing glory, which comes from the Lord, who is the Spirit."
The Charismatic movement, with its emphasis on dreams and visions, feelings and experiences, and new revelation, is one form of Christian mysticism. Because we have God’s completed Word, we are not to seek after dreams and visions or extra revelation from God. While it is possible for God to reveal Himself in dreams and visions today, we should beware the subjective nature of feelings and spiritual impressions.
It is vital to remember that anything a Christian experiences must line up with the truth of the Bible. God will not contradict Himself. He is not the author of confusion (1 Corinthians 14:33). God is certainly beyond our full comprehension, and there is much that is mysterious about Him. But He has revealed Himself to us. Rather than seek out mystical experiences, we should involve ourselves in the things God has revealed to us (Deuteronomy 29:29). Ephesians 1:3–14 talks about spiritual blessings in Christ. In part, that passage says, "[God] made known to us the mystery of his will according to his good pleasure, which he purposed in Christ, to be put into effect when the times reach their fulfillment—to bring unity to all things in heaven and on earth under Christ" (v. 9–10). God has revealed mystery and calls us to faithfully walk in His ways as He completes His plan (John 15:1–17; Philippians 3:20–21; 2 Corinthians 5:16–21).
Second Peter 1:3–8 sums up our call nicely: "His divine power has given us everything we need for a godly life through our knowledge of him who called us by his own glory and goodness. Through these he has given us his very great and precious promises, so that through them you may participate in the divine nature, having escaped the corruption in the world caused by evil desires. For this very reason, make every effort to add to your faith goodness; and to goodness, knowledge; and to knowledge, self-control; and to self-control, perseverance; and to perseverance, godliness; and to godliness, mutual affection; and to mutual affection, love. For if you possess these qualities in increasing measure, they will keep you from being ineffective and unproductive in your knowledge of our Lord Jesus Christ." There is mystery, yet the way in which we are called to live is not at all mysterious. Study the Word, seek to honor God, and allow His Holy Spirit to work within you.