According to Lama Surya Das co-meditation means, essentially, meditating with. This includes yet goes beyond human relationships. This kind of connection and meditation allows us to enter into the tantric world of non-separation and oneness, completeness, totality, what Buddhists generally call no duality (not two).

1. According to Lama Surya Das co-meditation means, essentially,
meditating with. This includes yet goes beyond human relationships.
This kind of connection and meditation allows us to enter into the
tantric world of non-separation and oneness, completeness, totality,
what Buddhists generally call no duality (not two). It allows us to
meditate with everything, exploit and integrate every single thing—
outer, inner, and subtlest into the contemplative process.
Co-meditation
According to Lama Surya Das

2. This the warp and woof of everyday reality with all its polarities and
dichotomies, choices, attractions and antipathies becomes the very weft of the
spiritual weave which, like the good earth (dhrm, in Sanskrit) upholds us. This
dhrm is the root of the word dharma or truth, the fundament, the way and
wisdom itself.
Co-meditation is generally known as Cross Breathing. The easy principle on
which it is based is that, depending on the type of respiration used, the mental
condition will be inspired in that particular way. Co-meditation is believed to
reduce stress and suffering. Co-meditation helps normalize the heart rate, blood
pressure and anxiety.
Co-meditation has been practiced for centuries by lamas, physicians and
common people to clear and quiet the minds and emotions of dying lamas. Co-
meditation puts the mind in a deep state of relaxation. Even Tibetan Buddhist
lamas practice it to calm their minds and emotions.

3. It eases the lamas’ ability to enter into meditative conditions and helps them
bring control over panic and illness.
The way of co-meditation, though focused on the sickly person, is intended also
to be helpful in comforting the helper through such emotionally unsettling times.
Having something useful and real to do often helps helpers overcome the
common and often insufferable sense of helplessness experienced as they
accompany loved ones to the ends of their lives on earth.
The first benefit is one that Co-Meditation shares with other forms of
meditation: the sharpening of one’s ability to core awareness. Diligent and
consistent practice in focusing mind, as we work out a muscle, leads to greater
strength in the faculty being exercised. The worth of increasing this ability can
hardly be overestimated.

4. A second benefit of Co-Meditation: The increase of inner peace and clarity of
mind and heart. Individually conducted solo meditation techniques often
explicitly guide the practitioner in such a direction. The achievement of inner
peace and clarity through solo meditation is indisputably a marvelously
beneficial accomplishment.
A third benefit to be gained from Co-Meditation increases from the cure that
experience of Co-Meditation presents to those aspects of awareness that are
ready to self-centeredness. Rather than directing attention toward selfish
desires and anxieties, Co-Meditation gives experience of others when the mind
is at calm, when one’s scheming agendas are silent.
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