The aseity of God means God is Eternal. He always has been, and always will be. It means God is self-existent. He exists on His own. Nothing or nobody ever has, or will, help Him to exist. God created everything but no one created God.
We can know God by His self-disclosure to us. God reveals Himself in creation and nature, in scripture, by His Son, and through the ministry of the Spirit in believers.
Jesus is Immanuel, God with us. He is with us in our nature. He is with us as our Savior. He is with us as our ever-present Helper. And He will be with us face to face forever.
The coming of Jesus Christ was in fulfillment of the promises made to Abraham and David. He is the offspring of Abraham through Whom all the nations will be blessed. He is the Branch of David, would will reign eternally with wisdom and with justice.
The power of this chapter is in the first sentence: “Esther put on her royal robes and stood in the inner court of the king's palace, while the king was sitting on his royal throne.”