Musnad Ahmad 32:372

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Abu ‘Imran al-Jawni, who said: I heard Anas ibn Malik narrating from the Prophet, peace and blessings of Allah be upon him, who said: "Allah will say to the person with the lightest punishment among the people of the Fire: 'If you had everything that is on the earth, would you ransom yourself with it?' He will say: 'Yes.' Allah will say: 'I wanted from you what was easier than this while you were in the loins of Adam: that you should not associate anything with Me, but you refused except to associate with Me.'"