Prayer of the Heart

The Jesus Prayer (Greek: Η Προσευχή του Ιησού, i prosefchí tou iisoú; Syriac: ܨܠܘܬܐ ܕܝܫܘܥ ‎, Amharic, Geez and Tigrinya: እግዚኦ መሐረነ ክርስቶስ,Slotho d-Yeshu' , ) or "The Prayer" (Greek: Η Ευχή, i efchí̱ – literally "The Wish") is a short formulaic prayer esteemed and advocated especially within the Eastern churches:

Lord Jesus Christ, Son of God, have mercy on me, a sinner.

The prayer has been widely taught and discussed throughout the history of the Orthodox Church. The ancient and original form did not include the words, "a sinner," which were added later. It is often repeated continually as a part of personal ascetic practice, its use being an integral part of the eremitic tradition of prayer known as Hesychasm (Ancient Greek: ἡσυχάζω, isycházo, "to keep stillness"). The prayer is particularly esteemed by the spiritual fathers of this tradition (see Philokalia) as a method of opening up the heart (kardia) and bringing about the Prayer of the Heart (Καρδιακή Προσευχή). The Prayer of The Heart is considered to be the Unceasing Prayer that the apostle Paul advocates in the New Testament. St. Theophan the Recluse regarded the Jesus' Prayer stronger than all other prayers by virtue of the power of the Holy Name of Jesus.

While its tradition, on historical grounds, also belongs to the Eastern Catholics, and there have been a number of Roman Catholic texts on the Jesus' Prayer, its practice has never achieved the same popularity in the Western Church as in the Eastern Orthodox Church, although it can be said on the Anglican Rosary. As distinct from the prayer itself, the Eastern Orthodox theology of the Jesus' Prayer enunciated in the 14th century by St. Gregory Palamas was generally rejected by Roman Catholic theologians until the 20th century, but Pope John Paul II called Gregory Palamas a saint, cited him as a great writer, and an authority on theology and spoke with appreciation of Palamas's intent "to emphasize the concrete possibility that man is given to unite himself with the Triune God in the intimacy of his heart". In the Jesus' Prayer can be seen the Eastern counterpart of the Rosary, which has developed to hold a similar place in the Christian West.

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Wikipedia