Imam Sadiq (a.s) quoted on the authority of God's Prophet (a.s)
“Whoever commits a sin and laughs will enter the Fire (of Hell).”
عن الصادق (عليه السلام) قال
قال رسول الله (صلى الله عليه وآله): من أذنب ذنبا وهو ضاحك دخل النار.
Similar narrations
Thawāb al-Aʿmāl wa ʿiqāb al-Aʿmāl #8661. Imam Ja’far Sadiq (a.s.) narrates from his ancestors that the Holy Prophet (s.a.w.s.) said, “A person who laughs while committing a sin...