your question is nonsense (sorry, but it's a fact ! ) you will not power it at that voltage !!!
the Led is rated 3.2V to 3.8V at 750mA (according to the datasheet) - If you want to design something using it, you should use a power source which allows you to give it the power while making sure you won't exeed the current - If you plan to use a 18650, then do the math with a fully charged battery and use the right resistor - While the battery "discharge" (what is the english word ?) , the led will be less bright, and you'll need to charge the battery or replace it with a fully charged one -
Powering it without a resistor with a partially charged battery could have burnt it - It didn't probably because it did not last long, and maybe because the battery couldn't deliver too much current... you've been lucky - But be aware that, if it didn't burn, it might be damaged, and will probably won't run for years !
and...if you think we are assholes...hum... an asshole is useful (I should say... indispensable), an idiot is not 