I (God) have multiplied on to you (man) to whom we all shall be gathered
Quran 23.79 Quran 67.24

Not together but differently and individually because each person Karma is different
However, I am (God) your higher self,closer to you than your jugular vein – Quran 50.16

When you know your own self, you know me (God) – Spiritual sayings of Muhammed

When you (man) elevate your lower self and reach your higher self (nafs)

You (man) can join, merge and become union with me (God)
When you (man) become union with me (God) we both are one (Oneness)