The "Heart-Space" is the middle of the chest, that whole area.
Think about the times you have referred to your "Heart" area.
It is an area of the body we naturally know about, no matter your religion, it's a natural place, or a place of knowing.
ana

Adapted from The Spontaneous Fulfillment of Desire, by Deepak Chopra (Three Rivers Press).
Do this regularly so that this ritual can focus your attention and your intention.

Go to a quiet place where you are not likely to be disturbed for 15 minutes. Close your eyes, practice the primordial sound mantra–“so-hum”–for five minutes, placing your awareness on your breath.

After five minutes, put your mental awareness in the area of your heart, in the middle of your chest. With your attention on your heart, you may begin to feel your heart beating more strongly. This is normal. As you experience the beating of your heart, begin to also experience gratitude.
(Remember those pictures of Jesus with His Sacred Heart?ana)

The way to experience gratitude is to think of all the things, events, and relationships in your life for which you have reason to be grateful. Allow these images to surface in your consciousness while you keep your attention on your heart. Take a moment to think of all the people whom you love and all the people who share their love with you.

Then say to yourself: “Every decision I make is a choice between a grievance and a miracle. I let go of grievances and choose miracles.”

Certain resentments and grievances–and the people associated with those resentment and grievances–may surface in your awareness. If they do, just say, “I let go of the grievances. I choose the miracles.”

Then become aware of your heart again, and consciously start to breathe into your heart. As you do, say to yourself, “Love … knowingness … bliss … love,” and then breathe out for the same count of four. Between each inhalation and exhalation pause for several seconds. Do this for three or four times.

The fire of your soul–which is love, knowingness, and bliss–will start to broadcast itself through the heart. The fire of your soul now begins to create your intention.

Adapted from The Spontaneous Fulfillment of Desire, by Deepak Chopra (Three Rivers Press).
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The Maha Prajna Paramita Heart Sutra
Perceiving that all five skandhas are empty saves all beings from suffering.
Form does not differ from emptiness, emptiness does not differ from form.
Form is emptiness, emptiness is form.
No appearing, no disappearing.
No taint, no purity.
No increase, no decrease.
All dharmas are marked with emptiness.
No cognition—no attainment.
Nirvana.
Unexcelled perfect enlightenment—anuttara samyak sambodhi.
Gate, gate, paragate, parasamgate, bodhi svaha!
—From the Heart Sutra
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