Mettā (Pali) or maitrī (Sanskrit) means benevolence, loving-kindness, friendliness, amity, friendship, good will,kindness, and active interest in others. It is the first of the four sublime states (Brahmavihāras) and one of the ten pāramīs of the Theravāda school of Buddhism.
The cultivation of benevolence (mettā bhāvanā) is a popular form of meditation in Buddhism in the Theravadin Buddhist tradition. In the Tibetan Buddhist tradition, it is part of the Brahmavihara meditation (four immeasurables). Metta as ‘compassion meditation’ is often practiced in Asia by broadcast chanting, wherein monks chant for the laity.
The compassion and universal loving-kindness concept of Metta is discussed in the Metta Sutta of Buddhism, and is also found in the ancient and medieval texts of Hinduism and Jainism as Metta or Maitri.
Small sample studies on the potential of loving-kindness meditation approach on patients suggest potential benefits. However, peer reviews question the quality and sample size of these studies, then suggest caution.