It is narrated from Sayyiduna Wathilah bin al-Asqa' (may Allah be pleased with him) that he said: I heard the Messenger of Allah (peace and blessings be upon him) say: Allah, the Mighty and Majestic, says: "I am as My servant thinks of Me; so let My servant think as he wishes."
Hadith Referenceالمعجم الكبير للطبراني / باب الواو / 18431