Question:
As a teenager I wasn't the most scrupulous about giving masser though I tried to work on it many times I've had some fallouts. I kept accepting on myself to give masser even though I knew there were possibly reasons that I may be exempt (relying on others) never the less I resolved that I still want to commit( part of which I assume because I was being machmir and doing the better thing) My problem is I do not know how much I owe. Also after learning some of the halachos recently, it occured to me that I may have other exemptions (such as debt) so I was wondering if nevertheless I'm bound by my earlier resolving.
Thank you!
Answer:
Hello,
You should be matir neder, in order to rid your self of the stigma and sin of it being a neder. Then make a declaration that if you will be mekabel on yourself to give maaser, that it should be bli neder. All of this can be done by hatoras nedarim on erev Rosh Hashana.
Aside from this, if there is money that you owe to maaser (even if it is without a neder) try to approximate what it is, and give it, if you can.
It is possible that you have other exemptions, and it possible that you are not obligated to give maaser, however but this would have to be discussed separately.
Best wishes
