Abu Suhayl Nafi' bin Malik (may Allah have mercy on him) said that Umar bin Abd al-Aziz (may Allah have mercy on him) said to him: "What is your view about the Qadariyyah?" He said: "They should be asked to repent; if they repent, well and good, otherwise they should be killed." Umar (may Allah have mercy on him) said: "That was my view too. This one verse alone is sufficient: 'So indeed you and what you worship cannot lead anyone astray from Him, except one who is destined to burn in Hellfire.' [Surah al-Saffat: 161-163]"
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20884