What should i do when my boyfriend keeps accusing me?

My boyfriend kept accusing me of going through his cell phone, his bag and his pants pocket, he had relationship where women have gone through his personal things, he's accusing me of doing the same. it hurts. i found out some personal things about him, he thinks i got those information by going through his phone,pocket and bag, that's not the case. i found out through devices (gadgets) and on the internet. technology have increase you know. i hate it when he does that. what should i do or say?