Attributes are the revealed character of God, whatever God has in anyway revealed as being true of Himself. God wants to be known by His creatures, you and me, and has gone to great lengths to reveal Himself to us in creation, Scripture, and most of all in His Son, Jesus Christ.
In an introduction to his book, Attributes of God, A.W. Pink writes the following:
“The foundation of all true knowledge of God must be a clear mental apprehension of His perfections as revealed in Holy Scripture. An unknown God can neither be trusted, served, nor worshipped. In this booklet an effort has been made to set forth some of the principal perfections of the Divine character. If the reader is to truly profit from his perusal of the pages that follow, he needs to definitely and earnestly beseech God to bless them to him, to apply His Truth to the conscience and heart, so that his life will be transformed thereby.
Something more than a theoretical knowledge of God is needed by us. God is only truly known in the soul as we yield ourselves to Him, submit to His authority, and regulate all the details of our lives by His holy precepts and commandments. "Then shall we know, if we follow on (in the path of obedience) to know the Lord" (Hosea 6:3). "If any man will do His will, he shall know" (John 7:17). "The people that do know their God shall be strong" (Dan. 11:32).”
So what has God revealed about Himself to us in Scripture?
First, God is Spirit, invisible, without body or bodily parts, not like man or any other creature. The word “Spirit” removes God’s nature from all association with material and corporal organization.
A.W. Pink writes;
"In the beginning, God" (Gen. 1:1). There was a time, if "time" is could be called, when God, in the unity of His nature (though subsisting equally in three Divine Persons), dwelt all alone. "In the beginning, God." There was no heaven, where His glory is now particularly manifested. There was no earth to engage His attention. There were no angels to hymn His praises; no universe to be upheld by the word of His power. There was nothing, no one, but God; and that, not for a day, a year, or an age, but "from everlasting."
During a past eternity, God was alone: self-contained, self-sufficient, self-satisfied; in need of nothing. He changes not (Mal. 3:6), therefore His essential glory can be neither augmented nor diminished.”
Second, God exists in Himself and of Himself. His being He owes to no one. His substance is indivisible. He has no parts but is single in His unitary being.
AW Tozer writes in Knowledge of the Holy;
“The doctrine of divine unity means not only that there is but one God, it means also that God is simple, uncomplex, one with himself. The harmony of His being is the result not of a perfect balance of parts but of the absence of parts. Between His attributes no contradiction can exist. He need not suspend one to exercise another, for in Him all His attributes are one.
All of God does all that God does; He does not divide Himself to perform a work, but works in total unity of being.
The divine attributes are what we know to be true of God. He does not possess them as qualities; they are how God is as He reveals Himself to His creatures. Love, for instance, is not something God has which may grow or diminish or cease to be. His love is the way God is, and when He loves He is simply being Himself. Likewise with the other attributes.”
An attribute, then, is a part of God. It is how God is. In as much as finite human beings can comprehend and reason, we may say it is what God is.