Magic rules lightning bolt does this make sense

[ZebraDroid]

At a game today me and my friend were both at 1 life, I cast a lightning bolt and brought him to 0 life so he should lose but he said he was casting his own lightning bolt and that I lose because whats last is what matters but not sure if it makes sense because I cast my lightning bolt first so he should lose?

[Arix]

He's right. When you cast your Bolt, it doesn't happen immediately - it goes on the stack and waits to resolve. Your opponent gets a chance to respond, so in response, he plays his Bolt. Assuming neither of you do anything else, his Bolt resolves first, dealing 3 to you. State-based actions then see you at 0 life and cause you to lose before your Bolt can resolve.