Abu Musa Al-Ash'ari (May Allah be pleased with him) reported:
We accompanied the Prophet (ﷺ) in a journey, and when we climbed up a height, we proclaimed aloud: "La ilaha illallah (There is no true god except Allah)" and "Allahu Akbar (Allah is Greatest)." The Prophet (ﷺ) admonished us saying, "O people, take it easy. He Whom you are calling is not deaf or absent. He is with you (i.e., by His Knowledge), He is Hearing and He is Near."[Al-Bukhari and Muslim].
App reference: Book 8, Hadith 24
Arabic/English book reference: Book 8, Hadith 979