God, the All-Mighty, Merciful and Compassionate, revealed in the Qur'an that He is close to man and will answer people when they pray to Him. One of the relevant verses is as follows:
If My servants ask you about Me, I am near. I answer the call of the caller when he calls on Me. They should therefore respond to Me and believe in Me so that they will be guided aright. (Surat al-Baqara: 186)
As stated in the verse above, God is close to everybody. He has knowledge of everyone's wishes, feelings, thoughts, every word uttered, anything whispered and even what is concealed deep in one's thoughts. Consequently, God hears and knows everyone who turns to Him and prays to Him. This is God's blessing on mankind, and a manifestation of His mercy, grace and infinite power.