Since [the] perfections characterize God, they cannot be discovered and defined by man, especially in his depravity, for man by himself cannot know God completely. Rather, God must reveal Himself for man to assuredly know anything about God, including His perfections. God has revealed Himself in nature, but humanity corrupts that knowledge. Only the Bible gives accurate information about God and His perfections. Even this information is not exhaustive, but it is true because it is written in the inspired text.
John MacArthur