Ñ(IX,109): One who wants to develop these four should practise them towards beings first as the promotion of the aspect of welfare—and lovingkindness has the promotion of the aspect of welfare as its characteristic;
Tato evaṃ patthitahitānaṃ sattānaṃ dukkhābhibhavaṃ disvā vā sutvā vā sambhāvetvā vā dukkhāpanayanākārappavattivasena, dukkhāpanayanākārappavattilakkhaṇā ca karuṇā.
Ñ: and next, on seeing or hearing or judging that beings whose welfare has been thus wished for are at the mercy of suffering, they should be practised as the promotion of the aspect of the removal of suffering—and compassion has the promotion of the aspect of the removal of suffering as its characteristic;
Athevaṃ patthitahitānaṃ patthitadukkhāpagamānañca nesaṃ sampattiṃ disvā sampattipamodanavasena, pamodanalakkhaṇā ca muditā.
Ñ: and then, on seeing the success of those whose welfare has been wished for and the removal of whose suffering has been wished for, they should be practised as being glad—and gladness has the act of gladdening as its characteristic;
Ñ: but after that there is nothing to be done and so they should be practised as the neutral aspect, in other words, the state of an onlooker—and equanimity has the promotion of the aspect of neutrality as its characteristic;
Tasmā ito hitādiākāravasā panāsaṃ paṭhamaṃ mettā vuttā, atha karuṇā muditā upekkhāti ayaṃ kamo veditabbo.
Ñ: therefore, since their respective aims are the aspect of welfare, etc., their order should be understood to correspond, with lovingkindness stated first, then compassion, gladness and equanimity.