The four establishments of mindfulness and its sutta history - as well as the Bhikkhunupassaya Sutta - Directed and Undirected Meditation (SN: 47:10). Suttas available here: https://a-buddha-ujja.hu/sn-47.3/en/bodhi) and here https://www.accesstoinsight.org/tipitaka/sn/sn47/sn47.010.olen.html
Steady the heart by not picking up the signs of crisis or anxiety. Instead use the simple and steady body rhythms and signs that hold the heart. Make the heart the priority.
In the sensory world, boundaries, signs of separation and comparisons must be experienced. But entering the heart realm, we can experience the boundlessness of the brahma vihara.
In meditation we open an energy domain with discernable material and immaterial aspects. We meet, widen and soften to this experience, providing a pragmatic healing and protection against life's vicissitudes.
