There is the Carnal, Vulgar Greatness of wealth, adulation and power which issues from Pride, Vanity, Lust and Deceit. See LouisXIV who repealed the Edict of Nantes, a guarantee of tolerance to French protestants, in 1685.
Then there is the Greatness of God which proceeds from His essence. He is Love. He is Good. He is Life. He is Giver. He is Saviour. He is Healer. He is Beginning. He is End. He is Eternal. He is I AM.
The Sin in the garden was the Sin of Lucifer. "I will attain the Greatness of God outside of God".
That Sin has always been the one that separates us from God. Not the swearing, not the drinking, not the womanizing, not the drug abuse, not the thievery, not the murdering nor any other Physical act. They are manifestations of the core Sin of Rebellion against God which is self-worship which is Idolatry.
God created us for Greatness. It is His desire for us to Manifest His Greatness - to put it on - to Walk in it - to Talk from it - to Work in it.
To whom God would make known what is the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory: -
Fear not, little flock; for it is your Father's good pleasure to give you the kingdom. -
Behold, what manner of love the Father has bestowed upon us, that we should be called the sons of God: therefore the world knows us not, because it knew him not.
Beloved, now are we the sons of God, and it does not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is. -
The eyes of your understanding being enlightened; that you may know what is the hope of his calling, and what the riches of the glory of his inheritance in the saints, -
These verses tell us about the Greatness of God in Giving to us His Glory. That Glory Manifests in us by His Holy Spirit in us. So, the Greatness of our Glory is actually the Greatness of His Glory manifested through us.
To Him belongs all Praise, all Glory and all Honour both now and Forever!