Barbacking in a relationship

Both my boyfriend and I have been together for a very long time and we've both been tested. We are both clear of anything! He really wants to fuck me without a condom, I was always told by my mom that if a gay guy has sex without a condom hell die. Now obviously I know I'm not going to die but is it okay to have sex without a condom if you're both clean of any type of std or hiv?