il y va de cet être même en son être (EtreTemps)
it is concerned in its being about this very being (BT)

NT: It is concerned in its being about this very being (es geht in seinem Sein um dieses Sein selbst, the formally indicative formula for Seinsverständnis usually said of dative Da-sein), 12, 42, 52f, 84, 104, 123, 133-5, 141, 143, 153, 153fn, 179, 191-193, 231f, 235, 250, 257, 263 (ownmost being), 287, 289, 297, 313, 322, 325, 406; the being of this concern is in each case my own, 42. See also Mineness; Understanding of being (BTJS)

This is Aristotle’s Ethics ontologized. It is Heidegger’s first attempt to translate the self-referential or circular movement of πρᾶξις — human action par excellence since it is action for its own sake, such that it constitutes for Aristotle both the ἀρχή and τέλος of φρόνησις — into the ontological terms later familiar to us in the analysis of Dasein as “ein Seiendes, dem es in seinem Sein um dieses Sein selbst geht”: “a being which in its being goes about this being, is concerned about this being, has this being as an issue” (SZ 12 et passim). In BT, the phrase is first used to formally indicate the self-referential character of understanding. But in the early proto-context, the phrase introduces us to the genealogically more proximate biblical and Greek contexts, familiar to us from Heidegger’s religion courses, connecting concern or curare with the philosophical cliche, “life is hard.” This latter theme appears only indirectly in BT, in Everyone’s “tendency to take things lightly and make things easy” (SZ 127f.; also GA20:340/247). (KisielBT:537)