It is narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "When the call to prayer (adhan) is given, Satan flees while passing wind so that he does not hear the adhan. When the adhan is finished, he returns. When the iqamah (second call to prayer) is pronounced, he flees again, and when the iqamah is finished, he comes back to cast doubts into the heart of the worshipper, saying, 'Remember such-and-such, remember such-and-such,' things which he had not remembered before." Imam Darimi (may Allah have mercy on him) said: In this hadith, by «ثوُبَ» is meant: «أقيم», that is, the iqamah.
Hadith Referenceسنن دارمي / من كتاب الصللاة / 1238
From this hadith, the virtue of the adhan (call to prayer) is understood, and also that the adhan and iqamah (second call to prayer) cause the shaytan to flee, and his task is to cast whispers (waswasah) during prayer. Furthermore, the one who hears the adhan and iqamah should repeat what the mu’adhdhin (caller) says, and in response to «حي على الصلاة» and «حي على الفلاح», it is sunnah to say «لا حول ولا قوة إلا باللّٰه».