✅ Answer: Pay attention to the following narrations:

1 عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ الْحَجَّالِ عَنْ ثَعْلَبَةَ بْنِ مَیْمُونٍ عَنْ یَحْیَی بْنِ طَلْحَةَ عَنْ سَوْرَةَ بْنِ کُلَیْبٍ قَالَ سَأَلْتُ أَبَا جَعْفَرٍ عَنْ أَدْنَی مَا یُجْزِئُ مِنَ التَّشَهُّدِ قَالَ الشَّهَادَتَانِ

📚 Al-Kafi, Vol. 3, p. 337

Surah ibn Kulayb said: 'I asked Imam Baqir (peace be upon him) about the minimum amount of Tashahhud.' The Imam said: 'Two testimonies!'

2 عَنْ حَمَّادِ بْنِ عِیسَی عَنْ حَرِیزٍ عَنْ أَبِی بَصِیرٍ وَ زُرَارَةَ جَمِیعاً قَالَا فِی حَدِیثٍ قَالَ أَبُو عَبْدِ اللَّهِ إِنَّ الصَّلَاةَ عَلَی النَّبِیِّ صلی الله علیه و آله مِنْ تَمَامِ الصَّلَاةِ (إِذَا تَرَکَهَا مُتَعَمِّداً) فَلَا صَلَاةَ لَهُ إِذَا تَرَکَ الصَّلَاةَ عَلَی النَّبِیِّ صلی الله علیه و آله

📚 Wasa'il 30-volume, Vol. 6, p. 407

Imam Sadiq (peace be upon him) said: 'Indeed, blessings upon the Prophet (peace be upon him and his family) are among the perfecters of prayer. If one intentionally abandons it, there is no prayer for him, when he abandons blessings upon the Prophet (peace be upon him and his family)!'

3 عَنْ حُمَيْدِ بْنِ شُعَيْبٍ عَنْ جَابِرِ الْجُعْفِيِّ قَالَ سَمِعْتُ أَبَا عَبْدِ اللَّهِ يَقُولُ: إِذَا صَلَّى أَحَدُكُمْ فَنَسِيَ أَنْ يَذْكُرَ مُحَمَّداً وَ آلَهُ فِي صَلَاتِهِ سُلِكَ بِصَلَاتِهِ غَيْرَ سَبِيلِ الْجَنَّةِ وَ لَا تُقْبَلُ صَلَاةٌ إِلَّا أَنْ يُذْكَرَ فِيهَا مُحَمَّدٌ وَ آلُ مُحَمَّدٍ

📚 Kitab Ja'far ibn Muhammad ibn Shurayh, p. 72

Jabir said: 'I heard Imam Sadiq (peace be upon him) say: 'When one of you prays and forgets to mention Muhammad and his family in his prayer, his prayer is taken on a path other than Paradise, and no prayer is accepted unless Muhammad and the family of Muhammad are mentioned in it!'

4 عَنِ الْحُسَیْنِ بْنِ سَعِیدٍ عَنْ صَفْوَانَ عَنْ مَنْصُورٍ عَنْ بَکْرِ بْنِ حَبِیبٍ قَالَ قُلْتُ لِأَبِی جَعْفَرٍ أَیَّ شَیْءٍ أَقُولُ فِی التَّشَهُّدِ وَ الْقُنُوتِ قَالَ قُلْ بِأَحْسَنِ مَا عَلِمْتَ فَإِنَّهُ لَوْ کَانَ مُوَقَّتاً لَهَلَکَ النَّاسُ

📚 Al-Kafi, Vol. 3, p. 337

Bakr ibn Habib said: 'I said to Imam Baqir (peace be upon him): 'What should I say in the Tashahhud and the Qunut?' He said: 'Say the best thing you know (in the Tashahhud and the Qunut), because if there was a specific and limited thing in the Tashahhud and the Qunut, the people would be destroyed!'

5 قَالَ الصَّادِقُ کُلُّ مَا نَاجَیْتَ بِهِ رَبَّکَ فِی الصَّلَاةِ فَلَیْسَ بِکَلَامٍ

📚 Man la Yahduruhu al-Faqih, Vol. 1, p. 317

Imam Sadiq (peace be upon him) said: 'Whatever you whisper to your Lord with in prayer is not 'Kalam' (i.e., speech that harms the prayer)!'

6 عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ قَالَ: قُلْتُ لِأَبِی عَبْدِ اللَّهِ التَّشَهُّدُ فِی الصَّلَاةِ قَالَ مَرَّتَیْنِ قَالَ قُلْتُ : وَ کَیْفَ مَرَّتَیْنِ قَالَ إِذَا اسْتَوَیْتَ جَالِساً فَقُلْ أَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَحْدَهُ لَا شَرِیکَ لَهُ وَ أَشْهَدُ أَنَّ مُحَمَّداً عَبْدُهُ وَ رَسُولُهُ ثُمَّ تَنْصَرِفُ قَالَ قُلْتُ: قَوْلُ الْعَبْدِ التَّحِیَّاتُ لِلَّهِ وَ الصَّلَوَاتُ الطَّیِّبَاتُ لِلَّهِ قَالَ هَذَا اللُّطْفُ مِنَ الدُّعَاءِ یَلْطُفُ الْعَبْدَ رَبُّهُ.

📚 Al-Tahdhib, Vol. 2, p. 101

Muhammad ibn Muslim said: 'I said to Imam Sadiq (peace be upon him): 'What is the Tashahhud in prayer?' He said: 'When you are sitting upright, say:

أَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَحْدَهُ لَا شَرِیکَ لَهُ وَ أَشْهَدُ أَنَّ مُحَمَّداً عَبْدُهُ وَ رَسُولُهُ

'I testify that there is no god but Allah, alone, with no partner, and I testify that Muhammad is His servant and messenger.'

Then you give the greeting!'

I said: 'So what is it when the servant says in the Tashahhud: 'Greetings are for Allah and the good blessings are for Allah'?' The Imam said: 'This is a grace from supplication that the Lord grants His servant success in!'

✅ According to the above narrations and others, some things, such as the two testimonies (Shahadatayn) and blessings (Salawat), are obligatory in the Tashahhud of prayer. But given that, according to narration 4, the Tashahhud is not a specific and limited thing, a person can also say other good phrases and supplications that are correct and appropriate for the state of prayer in his Tashahhud. Therefore, if a person combines several of the Tashahhuds transmitted from the Ahl al-Bayt (peace be upon them) in his Tashahhud to benefit from the contents of all of them, there is no prohibition or objection, and his prayer is correct.

اللَّهُمَّ فَصَلِّ عَلَی مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ لِوَلِیِّکَ الْفَرَجَ وَ الْعَافِیَةَ وَ النَّصْرَ