A form of “breath prayer,” the Jesus Prayer is usually said, “Lord Jesus Christ, Son of God, have mercy on me, a sinner,” while inhaling on the first half of the sentence and exhaling on the second half. According to Eastern Orthodox Church theology, the whole message of the Bible is encapsulated in the Jesus Prayer. However, the words may also be shortened to “Lord Jesus Christ, have mercy on me,” or even “Christ, have mercy.”
For millennia, Eastern Orthodox Christians have used the Jesus Prayer to obey the biblical instruction to “pray continually” (1 Thess 5:17). For some, by continuous repetition of the Jesus Prayer, inner peace and Christ’s presence are experienced in the heart. The Jesus Prayer is also a way for God’s people to “hide” or “treasure” the Word in their hearts (Ps 119:11). Though this psalm refers to the word(s) of God’s Law, Jesus is also the Word and is the fulfillment of the Law.
In Scripture, both the Hebrew word ruach and the Greek word pneuma can be translated “spirit,” “breath,” or “wind.” Use breath prayer to receive (inhale) from God and to express (exhale) your requests to and for God. While praying and inhaling, remember God breathing life into man’s nostrils (Gen 2:7). 
Breathe in the abundant Life of God. Remember Jesus breathing the Holy Spirit into his disciples (Jn 20:22). Receive the full and generous gift of God’s Spirit. While praying and exhaling, deliberately surrender your breath of life and your will to God.
Other words may be substituted in breath prayer, such as “Holy Spirit, fill me;” “Abba Father, I love you;” or “Christ Jesus, show me your truth.” Use whatever words God gives you. After discerning the prayer for you, stay with the same words for at least a month. Do not switch often. Instead, watch and wait for God’s response. The Jesus Prayer is a Prayer of the Heart, meant to express deep, ongoing declarations and requests to God. In contrast, prayers of petition and intercession address more rapidly changing needs and thoughts.
With God’s help, examine your heart before beginning. What do you want? Be truthful in requesting what you want. Prayer is not a technique nor a transaction but an interaction with God. If you want Christ to have mercy on you, pray these words. If you want to love God more, pray this request.
The goal here is not mere repetition of words in order to empty your mind. Instead of emptying your mind in breath prayer, let your mind, heart, and body be filled with the Holy Spirit of Christ. The goal here is not just to feel peaceful or less anxious. Instead of seeking more peacefulness, seek the Prince of Peace.
Start with praying the Jesus Prayer for ten continuous minutes a day. Focus on the words while turning your heart towards God. Then schedule one- to two- minute breaks in the midst of your day to pray the Jesus Prayer. Next begin to pray as you go—as you drive, walk or ride bike. Gradually, take this prayer into everyday activities as a constant reminder of God’s presence, sovereignty and provision and of your desire for Him.
Colossians 4:2: Devote yourselves to prayer, being watchful and thankful. Ephesians 6:18: And pray in the Spirit on all occasions with all kinds of prayers and requests. (NIV)