During thashahhud I’ve always been saying:
التَّحِيَّاتُ الْمُبَارَكَاتُ الصَّلَوَاتُ الطَّيِّبَاتُ لِلَّهِ ، السَّلامُ عَلَيْكَ أَيُّهَا النَّبِيُّ وَرَحْمَةُ اللهِ وَبَرَكَاتُهُ، السَّلامُ عَلَيْنَا وَعَلَى عِبادِ اللهِ الصَّالِحِينَ أَشْهَدُ أَنْ لَا إِلَهَ إلاّ اللهُ، وَأَشْهَدُ أَنَّ مُحَمَّداً وَرَسُولُ اللهُ
but today i saw in islamqa.info that the soundest version is:
“At-tahiyyaatu Lillaahi wa’s-salawaatu wa’t-tayyibaat, as-salaamu ‘alayka ayyuha’n-Nabiyyu wa rahmat-Allaahi wa barakaatuhu. As-salaamu ‘alayna wa ‘alaa ‘ibaad-Illaah is-saaliheen. Ash-hadu an laa ilaaha ill-Allaah wa ash-hadu anna Muhammadan ‘abduhu wa rasooluhu ”
So have I been saying it wrong this entire time? Were my prayers valid? Is it okay to say one of these versions and not just that one?
Also the one that islamqa mentioned was narrated by Abdullah Ibn Masood رضى الله عنه and his status is known very well...though other versions were narrated by Ibn Umar and Abdullah Ibn abaas رضى الله عنهم and they are also known for their lofty status in matters of knowledge, also Imaam Ahmad رحمة الله عليه, narrated and used the one mentioned by Abdullah Ibn masud or that's in islamqa.
However as per shaykh Al Islam ibn Taymiyyah رحمة الله عليه, it's best to use all three of them in between alternatively to practice all the sunnahs or sayings the prophet said...if the prophet used all these three versions then we should also use sometimes the most narrated one and sometimes the other two.
But anyway your prayers are valid because it's from sunnah too so don't be afraid
و الله اعلم