Magic Forums

I've heard it's said that if you kill a spider, it brings bad luck.

Now I don't know if this is true or not, but I always end up killing them out of general fear; either fear of being bit/or just cause some look poisonous etc, did not wanna take risks.

Now I've been seeing black spiders on three different thresholds (near the door) of three different entrances in my home.
This kinda reminded me of another superstition that says:

"If a spider drops onto a threshold, someone will die."

Now, can anyone tell me if I should take both of these superstitions serious or not? ..Your thoughts?