The Argentina star revealed that his only wish as a little boy was to become a professional player and said he will forever be grateful to the Blaugrana for making it happen
The Argentina international joined Barca at the age of 13 and has won the Ballon d'Or three times since making his debut in 2004.
Messi says that he always dreamt of playing football at the highest level and spoke of Barcelona's importance in making that happen.
"Since I was three or four years old, I dreamt of becoming a footballer," he told Caracol TV. "I was walking around with a football and all I wanted was to play.
"My only thought was to become a footballer, I did not think about doing anything else. If I could not have become one, I actually do not know what I would be today.
"I do not know what Barcelona saw in me, but I will always be grateful to them for what they did and what they keep doing.
"At that time, I was on a very expensive medical treatment and they covered all the costs and gave me the opportunity to play.
"This was something very beautiful, because they allowed me to realise my dream."
Messi then advised young players to not drop out of school and revealed the advice that his parents used to give him when he was a child.
"When I was a kid, I did not like to study much and they insisted that I kept studying because it was important," the Argentine explained.
"Now, I see that they were right, that it is good that one has studied. You never know what could happen in football.
"Every kid dreams of playing in the Primera Division, but not everyone can make it, so studying could be very important."