"He is the First," meaning: before everything, "and the Last" after everything, "and the Manifest," meaning: the Knower of what is manifest, "and the Hidden," meaning: the Knower of what is hidden.
﴿هُوَ الأول﴾ يَعْنِي: قبل كل شَيْء ﴿وَالآخِرُ﴾ بعد كل شَيْء ﴿وَالظَّاهِر﴾ يَعْنِي: الْعَالم بِمَا ظهر ﴿وَالْبَاطِنُ﴾ يَعْنِي: الْعَالم بِمَا بطن.