I. There is but one only, living, and true God, who is infinite in being and perfection, a most pure spirit, invisible, without body, parts, or passions; immutable, immense, eternal, incomprehensible, almighty, most wise, most holy, most free, most absolute; working all things according to the counsel of his own immutable and most righteous will, for his own glory; most loving, gracious, merciful, long-suffering, abundant in goodness and truth, forgiving iniquity, transgression, and sin; the rewarder of them that diligently seek him; and withal, most just, and terrible in his judgments, hating all sin, and who will by no means clear the guilty."
II. God has all life, glory, goodness, blessedness, in and of Himself; and is alone in and unto Himself all-sufficient, not standing in need of any creatures which he has made, nor deriving any glory from them, but only manifesting his own glory in, by, unto, and upon them. He is the alone fountain of all being, of whom, through whom, and to whom are all things; and has most sovereign dominion over them, to do by them, for them, or upon them whatsoever Himself pleases. In his sight all things are open and manifest, his knowledge is infinite, infallible, and independent upon the creature, so as nothing is to Him contingent, or uncertain. He is most holy in all his counsels, in all his works, and in all his commands. To Him is due from angels and men, and every other creature, whatsoever worship, service, or obedience he is pleased to require of them.
Resources
Who is God? WCF 2.1, Part 1 by Derek Thomas
Who is God? WCF 2.1, Part 2 by Derek Thomas
Westminster Confession of Faith chapters 2 – 5 - Theology Proper by Bob Burridge
The Being of God by Thomas Watson
What is God? by John Flavel
The Attributes of God (eBook) by A. W. Pink
The Existence and Attributes of God (eBook) by Stephen Charnock
The Doctrine of God (eBook) by Louis Berkhof
God Possesses All Possible Perfections by Robert Shaw
The Attributes of God (eBook) by Thomas Watson
The Attributes of God (eBook) by Sam Storms
One True God: A Biblical Study of the Doctrine of God (.pdf) by Paul Washer
Theology of the Westminster Confession (slides)
Of God and the Holy Trinity by John Battles (.pdf)
The Essence of God by Wilhelmus à Brakel
On God's Being a Spirit by Stephen Charnock
Of God and His Perfections by Thomas Boston
What is God? by Matthew Henry
What is God? by Thomas Vincent
What is God? by John Whitecross
What is God? by Alexander Whyte
Multimedia
The Attributes of God (16-Part Video Series) by Steve Lawson
Of God, and of the Holy Trinity (Ch.2, Sec.1) by Greg Bahnsen
Of God, and of the Holy Trinity (Ch.2, Sec.1) by Greg Bahnsen
Of God, and of the Holy Trinity (Ch.2, Sec.1-2) by Greg Bahnsen
Of God, and of the Holy Trinity (Ch.2, Sec.1-2) by Greg Bahnsen
Of God, and of the Holy Trinity (Ch.2, Sec.2) by Greg Bahnsen
The Attributes of God (MP3 Series) by J. I. Packer
Advanced Teaching on Predestination, Providence, God's Attributes, The Trinity by Dr. Joel Beeke
Character and Attributes of God (MP3 Series) by Sinclair Ferguson
The Character of God (MP3 Series) by Eric Alexander
The Attributes of God (MP3 Lecture Series) by Brian Borgman
The 1689 on God (2.1) by Joe Thorn & Jimmy Fowler (Doctrine and Devotion Podcast)
Who is God (WCF 2.1) by The Jerusalem Chamber
God: Is He? Who Is He? Part 1 (MP3) by John MacArthur
God: Is He? Who Is He? Part 2 (MP3) by John MacArthur
The God Who Is Stubborn to Save (MP3) by Dr. Dale Ralph Davis
Who Is God? (MP3) by Henry Mahan
Who is God Besides the Lord? by Rev. Geoff Thomas
Who is God? (MP3) by John Blanchard
The Doctrine of God and Reformed Theology (YouTube) by R. C. Sproul
Before the Beginning: The Aseity of God (YouTube) by R. C. Sproul
Yesterday, Today and Tomorrow: The Immutability of God (YouTube) by R. C. Sproul
Holy, Holy, Holy (YouTube) by R. C. Sproul
The Lord Our God, The Lord is One: The Simplicity of God (audio, video) by Sinclair Ferguson
Who is God (MP3 Series) by Tim Keller
Books
Attributes of God by A.W. Pink
The Existence and Attrributes of God by Stephen Charnock
The Doctrine of God by Herman Bavinck