I don't know much about Sinead O'Connor other than she wrote a song called "Nothing Compares 2 U". To be honest, I recall nothing of the song other than it the melody was pleasant and that the title of the song was also the chorus. With the chorus running through my head, I realized that there are biblical truths that can be derived from the title, even without knowing what her original intentions of the song were.
Truth #1: We can memorize all of His words and try to comprehend all of His attributes, but Jesus Christ is in no way limited to what we think He will be like. Nothing compares to Jesus.
Truth #2: One day, whether we choose to believe on Him or not, we will stand before Him and have to give an accounting of every thought and deed we have ever had and done. And just like in the song title, He will not be comparing us with any other person other than Himself. Again, nothing compares to Jesus. You and I both won't make it to Heaven on our own.
Repent and put your trust in Jesus.