Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
ahmad-zuhd:2108ʿAbdullāh > Abū Maʿmar > Jarīr > Fuḍayl b. Abū Rufaydah

[Machine] 'Aasim ibn Hubayrah, one of Abdullah's companions, said to me, "When you finish the call to prayer and say 'There is no god but Allah,' then say 'And I am one of the Muslims.'"  

الزهد لأحمد:٢١٠٨حَدَّثَنَا عَبْدُ اللَّهِ حَدَّثَنِي أَبُو مَعْمَرٍ حَدَّثَنَا جَرِيرٌ عَنْ فُضَيْلِ بْنِ أَبِي رُفَيْدَةَ قَالَ

قَالَ لِي عَاصِمُ بْنُ هُبَيْرَةَ وَكَانَ مِنْ أَصْحَابِ عَبْدِ اللَّهِ إِذَا فَرَغْتَ مِنَ الْأَذَانِ فَقُلْتَ لَا إِلَهَ إِلَّا اللَّهُ فَقُلْ وَأَنَا مِنَ الْمُسْلِمِينَ