Narrated Anas:

The Prophet (s.a.w.a.) said, "My Lord says, 'If My slave comes nearer to me for a span, I go nearer to him for a cubit; and if he comes nearer to Me for a cubit, I go nearer to him for the span of outstretched arms; and if he comes to Me walking, I go to him running.' "

Abu Huraira reported Allah's Messenger (s.a.w.a.) as saying that Allah, the Exalted and Glorious, thus stated:

I am near to the thought of My servant as he thinks about Me, and I am with him as he remembers Me. And if he remembers Me in his heart, I also remember him in My Heart, and if he remembers Me in assembly I remember him in assembly, better than his (remembrance), and if he draws near Me by the span of a palm, I draw near him by the cubit, and if he draws near Me by the cubit I draw near him by the space (covered by) two hands. And if he walks towards Me, I rush towards him. This hadith has been narrated on the authority of A'mash with the same chain of transmitters, but there is no mention of these words: " He draws near Me by the space of a hand, I draw near him by the space (covered) by two hands."

Translation:

From Ahmad ibn Hanbal’s Musnad al-Imam Ahmad ibn Hanbal, Remaining Musnad of the Frequent Narrators – Musnad of Abu Hurayrah (may Allah be pleased with him):

7374 - Abu Mu’awiyah and Ibn Numayr narrated to us, saying: Shu’bah narrated to us, from al-A’mash, from Abu Salih, from Abu Hurayrah, who said: The Messenger of Allah (peace be upon him and his holy progeny) said: Allah, Mighty and Majestic, says: “I am with My servant when he remembers Me. If he remembers Me within himself, I remember him within Myself; and if he remembers Me in an assembly, I remember him in an assembly better than them. If he comes near to Me a handspan, I come near to him an arm’s length; and if he comes near to Me an arm’s length, I come near to him a fathom’s length. And if he comes to Me walking, I come to him running.” Ibn Numayr added in his narration: “I am as My servant thinks of Me, and I am with him when he remembers Me.”