Why aren't Sikhs allowed to use foul words or swear?
How does Guru jee wish a Sikh to conduct him/ herself?
AsI bolivgwV ivgwVh bol ]
asee bolavigaarr vigaarreh bol ||
We are foul-mouthed; we spoil everything with our foul words.
Guru Nanak Dev jee
kUVu boil ibKu KwvxI bhu vDih ivkwrw rwm ]
koorr bol bikh khaavanee bahu vadhhehi vikaaraa raam ||
Speaking falsehood, one eats poison, and the evil within increases greatly.
Guru Amar Daas jee
gurU kw isK gMd-vwkI nw hovYguroo kaa sikh ga(n)dhaavaakee naa hovai
The Sikh of the Guru should never speak disgusting speech.
Rehatnama Bhai Chaupaa Singh Jee
This Shabad is by Guru Nanak Dev Ji in Raag Aasaa on Pannaa 473
Shalok, First Mehl:
*nwnk iPkY boilAY qnu mnu iPkw hoie ]
naanak fikai boliai than man fikaa hoe ||
O Nanak, speaking insipid words, the body and mind become insipid.
*iPko iPkw sdIAY iPky iPkI soie ]
fiko fikaa sadheeai fikae fikee soe ||
He is called the most insipid of the insipid; the most insipid of the insipid is his reputation.
*iPkw drgh stIAY muih Qukw iPky pwie ]
fikaa dharageh satteeai muhi thhukaa fikae paae ||
The insipid person is discarded in the Court of the L
ord, and the insipid one's face is spat upon.
*iPkw mUrKu AwKIAY pwxw lhY sjwie ]1]
fikaa moorakh aakheeai paanaa lehai sajaae ||1||
The insipid one is called a fool; he is beaten with shoes in punishment. ||1||
scu bwxI scu sbdu hY jw sic Dry ipAwru ]
sach baanee sach sabadh hai jaa sach dhharae piaar ||
When you love the Truth, your words are true; they reflect the True Word of the Shabad.
Guru Amar Daas jee
AMqru inrmlu inrml bwxI hir gux shjy gwvixAw ]6]
a(n)thar niramal niramal baanee har gun sehajae gaavaniaa ||6||
Deep within, they are pure, and their words are pure as well; intuitively, they sing the Glorious Praises of the Lord. ||6||
gMFu prIqI imTy bol ]
ga(n)dt pareethee mit(h)ae bol ||
There is a bond between love and words of sweetness.
---
It will be nice if the sangat adds more Gurubanee to support this topic