an attribute of God. The idea of omnipresence is not that God is everything or that God is in everything. It is that everywhere you go, God is there. There is no place in creation where you can go to escape the presence of God.
The quality of being everywhere present at the same time
An attribute that God alone possesses, and meaning He is present everywhere at the same time. Note that this is more than just the ability to appear anywhere at any time or the ability to be many places at one time.
God is everywhere present. There is no place where God is not. God is All There Is.
Omnipresence is the ability to be present in every place at any, and/or every, time; unbounded or universal presence. It is related to the concept of ubiquity, the ability to be everywhere at a certain point in time.