by Reb Aharon Rubin, from Eye to the Infinite, shared with permission.
HE ONE TIME MEDITATION IS STATED IN THE TORAH is understood by our sages to refer to prayer: “And Isaac went out to meditate in the field”. Besides hinting at the afternoon prayer, Minchoh, this verse contains instruction and guidance for preparing for prophetic prayer meditation.
“And Isaac went out”. Evidently, it was the practice to go out of the village in order to pray or meditate. This is also apparent in other places in Scriptures. However, the deeper implication of this is disengagement from the corporeal, the first condition for prophetic connection. For prayer meditation to be efficacious, we must remove ourselves from the mundane, not only physically but also mentally divorcing from external responsibilities and ties. During our commune with the King of kings, nothing else matters.
That Isaac meditated “in the field” indicates the advantage of meditating in open, grassy spaces. The Zohar sees here a reference to the “Field of Apples”, the Kabbalistic term for the Garden of Eden, because prayer is a walk in “the Garden”, a time one can experience the “Voice of G-d walking in the Garden”. Hence, the kabbalists’ recommendation that one imagine oneself to be in the Garden of Eden when learning, praying or singing to G-d. This is not fantasy; it is visualising where one truly is.
עדן Eden means delight. This is the delight of the consciousness attaching to soul and the soul to its source. From this Eden-delight flows a נהר Nohor, a river of pure chochmoh-wisdom, that flows into the גן Gan, the Garden of Eden, one’s Inner Consciousness. During prayer, we enter this Garden. (The initial letters of עד"ן נה"ר ג"ן Eden Nohor Gan (Eden, River, Garden) forms ענ"ג Oneg – “pleasure”!) This Garden of Eden is not limited to a specific place. It is the spiritual soul of the world. It ‘fills’ the Earth as the soul ‘fills’ the body.
 Genesis, 24:63. See Targum ibid. Ibn Ezra and Rashbam offer an alternative interpretation. See also Meditation and Prayer by Rabbi Aryeh Kaplan (Weider, 1988) p. 101, for an in-depth analysis of this verse, in particular of the verb לשוח LoSuach – to meditate. (Though this is the only reference in the Pentateuch, there are other references in the Prophets and Writings.)
 Brochoth, 26b.
 See Ex. 9:29, 9:33, 19:17.
 However, formal prayer [as in the three prayers of the day] should generally not be done in the open air (see O.C. 90:5.)
 See Targum Yerushalmi, Genesis 24:63.
 Paraphrased from Gen. 3:8
 Introduction of Luchoth HaBrith on Sefer Bris Olom (R. Isaac Ashkenazi) by Rabbi Naftoli Herts. See also Eiruvin 19a.