GAMBLING (Arabic maisir, مسريل, qimar )قيمر
is forbidden in the Qur’an.
Surah ii 216: “They will ask thee concerning wine, and games of chance. Say both is a great sin, and advantage also to men but their sin is greater than their advantage.”
Surah v 93: “Only would Satan sow hatred and strife among you by wine and games of chance, and turn you aside from the remembrance of God, and from prayer; will ye not, therefore abstain from them?”
The evidence of a gambler is not admissible in a Muslim court of law because gaming is a great crime. (Hidayah li, p. 688.)

Based on Hughes, Dictionary of Islam