What’s meaning. b4lls

Testicles. Having "balls of steel" or "big balls" equates to being brave. They've used the number "4" in place of the letter "a" to censor the 'rude word' - like when people write "f**k" instead of "fuck". People sometimes substitute "1" for "i" or "l", "3" for "e", "4" for "a", "5" for "s", "7" for "t", and so on. For example, in 1337 ("Leet speak", c/f elite.) https://en.wikipedia.org/wiki/Leet

4 sorta looks like a slightly turned capital A. It's just "balls".

I wish I have balls of steel in rejecting people sometimes.