Hayan Abu Nadr reported,
Wathila bin Asqa visited Abu Aswad al-Jurashi during the illness from which he died. He greeted him and sat down. Abu Aswad took Wathila's right hand and wiped it over his eyes and face, because Wathila had pledged allegiance with it to the Messenger of Allah ﷺ.Wathila said to him, "There is one thing I want to ask you about."Abu Aswad replied, "What is it?"Wathila asked, "How do you think of your Lord?"Abu Aswad gestured with his head, meaning, well.Wathila said, "Then receive good news, for I heard the Messenger of Allah ﷺ say, 'Allah 
said, I am as My servant thinks of Me, so let him think of Me whatever he wishes.'"
Azami 3520
Sahihعن حيان أبي النضر قال
دخلت واثلة بن الأسقع مع على أبي الأسود الجرشي في مرضه الذي مات فيه فسلم عليه وجلس، قال: فأخذ أبو الأسود يمين واثلة فمسح بها على عينيه ووجهه لبيعته بها رسول الله ﷺ، فقال له واثلة: واحدة أسألك عنها. قال: وما هي؟ قال: كيف ظنك بربك؟ قال: فقال أبو الأسود: وأشار برأسه- أي حسن. قال واثلة: أبشر إني سمعت رسول الله ﷺ يقول: قال الله عز وجل: أنا عند ظن عبدي بي، فليظن بي ما شاء.
Imam Ahmad (16016) narrated it from Walid bin Muslim, who said, Walid bin Sulayman - that is, Ibn Abu Saaib - told me, saying, Hayan Abu Nadr told me, saying, then he related it.Tabarani also narrated it in Kabir (22/88) via a route through Walid bin Muslim with his chain of transmission, except that he did not mention the story. Tabarani narrated it in Awsat (403) through another route from Hayan Abu Nadr, who said, I met Wathila bin Asqa, and he said, I heard the Messenger of Allah ﷺ say, "I am as My servant thinks of Me. If he thinks well, then well, and if he thinks ill, then ill."Haythami cited it in Majma (2/318) from Hayan Abu Nadr, attributing it to Ahmad and to Tabarani in Awsat, and he said, "The men of Ahmad are trustworthy." He failed to attribute it to Kabir, which would have been more fitting since the two sources of extraction are the same.Then Tabarani narrated it in Awsat (7947) also through another route from Yunus bin Maysara bin Halabas, who said, We went in to visit Yazid bin Aswad, and Wathila bin Asqa came in to visit him, and he related something similar.Walid bin Muslim is a mudallis, but he stated explicitly that he heard it directly. Hayan Abu Nadr is al-Asadi al-Shami, whom Ibn Main deemed trustworthy, while Abu Hatim said, "Salih." His biography is found in Tarikh al-Kabir (3/55) and in Jarh wa Tadil (3/244-245).Ibn Hibban graded it sahih (633, 634, 635), and so did Hakim (4/240), both through another route from Hisham bin Ghaz, who said, Hayan Abu Nadr told us, from Wathila bin Asqa, and he related the hadith without the story. Hakim said, "Sahih in its chain of transmission."