ὁ ὢν καί ὁ ἦν καί ὁ ἐρχόμενος ho ṑn kaí ho ēn kaí ho erchómenos (G3801)

the one being and the one that was and the one coming, i.e. the Eternal, as a divine epithet of Christ

a phrase combining G3588 with the present participle and imperfect of G1510 and the present participle of G2064 by means of G2532;