How young is too young?

So in 29 this guy I’m talking to I found out he’s only 23. I’m having mixed feelings about going forward. My friend tells me age is just a number if he’s mature enough. Which i believe he is as he has a good job in construction, has his own place, his own car. Is in the works of buying a house and just seems so mature since the moment we’ve started to talk. I just don’t know if I should continue with talking to him. I feel weird with how much younger he is than me