Mettā, also known in common parlance as love.
Those who are skilled in the meaning of scripture
should practice as follows to realize the state of peace
let them be able and upright, very upright,
easy to speak to, gentle and humble;
content and unburdensome,
unbusied, living lightly,
alert, with senses calmed,
courteous, not fawning on families.
Let them not do the slightest thing
that others might blame with reason.
May they be happy and safe!
May all beings be happy!
Whatever living creatures there are
with not a one left out—
frail or firm, long or large,
medium, small, tiny or round,
visible or invisible,
living far or near,
those born or to be born—
may all beings be happy!
Let none turn from another,
nor look down on anyone anywhere.
Though provoked or aggrieved,
let them not wish pain on each other.
Even as a mother would protect with her life
her child, her only child,
so too for all creatures
unfold a boundless heart.
With love for the whole world,
unfold a boundless heart:
above, below, all round,
unconstricted, without enemy or foe.
When standing, walking, sitting,
or lying down while yet unweary,
keep this ever in mind;
for this, they say, is a meditation of Brahmā in this life.
Avoiding harmful views,virtuous,
accomplished in insight,
with sensual desire dispelled,
they never return to a womb again.
~ The Discourse on Love, a translation of the Metta-sutta
by Bhikkhu Sujato on SuttaCentral