Marriage is an enormous responsibility. Well I mean it sure make people hesitate a bit, as marriage is stereotyped with less freedom, boredom, trouble etc. I do not think that way, I say it depends on the relationship and on its values. Although, I know I will wait and think a while before doing this. It's not decidable in a few days, in my optinion.
---info: warning: I don't know your boyfriend. So from here and below I
cannot garantee that what I say is correct and reliable! Here below is mainly on my own thoughts. Thank you.---
anyway, as you know, men have a slower maturity as women. So it's normal that a boyfriend at 24 may freak a bit about marriage. Unfortunately, this won't help the situation about you wanting and him waiting.
Maybe he puts less importance into marriage as you do ? He does love you but the image of marriage is maybe disturbing to him. Maybe with time he'll do it, just not now, I think his mind isn't really into it. D'ont pressure him too much, this could have negative side-effects against you.
Again, I cannot garantee that this is correct, but that's probably how i'd feel.
Sk.