After wife Beyonce Knowles gave birth to baby daughter Blue Ivy Carter on Saturday (07.01.12), the 42-year-old rapper laid down new track 'Glory', in which he describes the new arrival as his "greatest creation".
Posting the song on his website Life and Times, the hip-hop star - real name Shawn Carter - raps on the track: "The most amazing feeling I feel, words can't describe what I'm feeling for real / Baby, I paint the sky blue, my greatest creation was you.
"You're the child of destiny / you're the child of my destiny / you're my child with the child from Destiny's Child."
The notoriously private star also alludes to the fact that he and the 'Halo' hitmaker may have suffered a miscarriage in the past, and describes his newborn daughter as "magic".
The lyrics continue: "Last time the miscarriage was tragic / We was afraid you'd disappear but nah baby you're magic."
Jay was by his wife's side as she delivered the tot via Caesarean section on Saturday, after checking in to New York's Lenox Hill Hospital under the pseudonym Ingrid Jackson.
The couple are thought to have paid $1.3 million to rent out the entire fourth floor of the hospital, while security was increased with staff reportedly being asked to turn in their phones and cameras were covered with tape.
According to the New York Daily News, the baby's moniker is believed to have a special meaning to the couple, with Jay's seminal 2001 album being titled 'The Blueprint', while 'Blue Magic' was the first single on his 2007 record 'American Gangster'.
Meanwhile, the 'Ivy' part of her name is said to be a play on the Roman numerals IV, the couple's most-cherished number.
While Beyonce's latest studio album was entitled '4', the pair also got married on April 4.
The singer has previously said: "We all have special numbers in our lives, and four is that for me. It's the day I was born, my mother's birthday, and a lot of my friends' birthdays are on the fourth. April 4 is my wedding date."