Good Manners and Form (Al-Adab)
Ṣaḥīḥ al-Bukhārī 6107
مَنْ حَلَفَ مِنْكُمْ فَقَالَ فِي حَلِفِهِ بِاللاَّتِ وَالْعُزَّى. فَلْيَقُلْ لاَ إِلَهَ إِلاَّ اللَّهُ. وَمَنْ قَالَ لِصَاحِبِهِ تَعَالَ أُقَامِرْكَ، فَلْيَتَصَدَّقْ
man ḥalafa minkum faqāla fī ḥalifihi bi-l-llāti wa-l-ʿuzzā. falyaqul lā ilaha illā-Llāh. waman qāla liṣāḥibihi taʿāla uqāmirka, falyataṣaddaq
Transliteration generated from the Arabic vowel marks
The full narration
Narrated Abu Huraira:Allah's Messenger (ﷺ) said: "Whoever amongst you swears, (saying by error) in his oath 'By Al-Lat and Al- Uzza', then he should say, 'None has the right to be worshipped but Allah.' And whoever says to his companions, 'Come let me gamble' with you, then he must give something in charity (as an expiation for such a sin)." (See Hadith No)
Source
Ṣaḥīḥ al-Bukhārī · 6107