The key to learning is repetition. The key to learning is repetition. The key to learning is repetition.
A multitude of explanations has been given as to how and why Psalms 14 and 53 are almost identical in content. Whether my explanation—the key to learning is repetition—is one of the actual reasons God had for repeating Himself cannot be definitively proven or disproven.
What we do know from numerous examples in Scripture (Lot’s wife being one of them) is that Jehovah only has to say something one time before humanity is expected to respond obediently. The God of heaven is not a nagger, and He never fails to keep His word, even if He only says it one time. So, if God says something once, it needs to be diligently heeded and carefully, precisely obeyed.
Just as many modern song books have the same lyrics set to different tunes, it appears that the Hebrew psalm book may have had the same thing in Psalms 14 and 53. Psalm 14’s superscription identifies it as a “psalm of David”; Psalm 53’s superscription states it to be “a contemplation (Maschil) of David”. The latter superscription also identifies the tune it is set to (“Mahalath”).
There are times and places in Scriptures in which God repeats himself. Jesus’ exhortation “he who has ears, let him hear” is found over a dozen times in the New Testament. It must be something quite important, an essential to spiritual success.
The key to learning is repetition: “The fool has said in his heart, ‘There is no God.’” (Psalm 14:1). “The fool has said in his heart, ‘There is no God.’” (Psalm 53:1).
Learn it and live accordingly.