Sovereignty is the supreme authority of God, his absolute right to rule over creation. He is not subject to any power or law outside of himself.
God has planned, has a purpose for, and is in complete control of every aspect of His creation, both good and bad, including our individual lives. He does this in such a way that He never authors or approves of sin or relieves man of his responsibility by violating his will. He does all for His glory and all He does in relation to those whom He chooses and loves is for their good.