It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) was taught opening and comprehensive words regarding goodness and virtue. For example, we did not know what we should recite in prayer; the Prophet (peace and blessings be upon him) taught us to say: «التَّحِيَّاتُلِلّٰهِوَالصَّلَوَاتُوَالطَّيِّبَاتُالسَّلَامُعَلَيْكَأَيُّهَاالنَّبِيُّوَرَحْمَةُاللّٰهِوَبَرَكَاتُهُالسَّلَامُعَلَيْنَاوَعَلَىعِبَادِاللّٰهِالصَّالِحِينَأَشْهَدُأَنْلَاإِلٰهَإِلَّااللّٰهُوَأَشْهَدُأَنَّمُحَمَّدًاعَبْدُهُوَرَسُولُهُ» "All verbal, physical, and bodily acts of worship are for Allah alone. O Prophet (peace and blessings be upon you), may peace, Allah's mercy, and blessings descend upon you. May peace descend upon us and upon the righteous servants of Allah. I bear witness that there is no deity except Allah and that Muhammad (peace and blessings be upon him) is Allah's servant and His Messenger."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 3877