(and he was not a liar) When Messenger of Allah ﷺ said, "Samiʿa l-lahu liman hamidah" none of us bent his back (for prostration) till the Prophet ﷺ prostrated and then we would prostrate after him.  

كَانَ رَسُولُ اللَّهِ ﷺ إِذَا قَالَ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ لَمْ يَحْنِ أَحَدٌ مِنَّا ظَهْرَهُ حَتَّى يَقَعَ النَّبِيُّ ﷺ سَاجِدًا ثُمَّ نَقَعُ سُجُودًا بَعْدَهُ  

When the Messenger of Allah ﷺ said: Allah listened to him who praised Him, none of us bent his back till he (the Holy Prophet) prostrated; we then, afterwards, went down in prostration.  

كَانَ رَسُولُ اللَّهِ ﷺ إِذَا قَالَ سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ لَمْ يَحْنِ أَحَدٌ مِنَّا ظَهْرَهُ حَتَّى يَقَعَ رَسُولُ اللَّهِ ﷺ سَاجِدًا ثُمَّ نَقَعُ سُجُودًا بَعْدَهُ  

[Machine] The translation of the passage into English is:

"When the Messenger of Allah ﷺ would raise his head from bowing, none of us would straighten his back until he prostrates, then we would prostrate."  

كَانَ رَسُولُ اللهِ ﷺ إِذَا رَفَعَ رَأْسَهُ مِنَ الرُّكُوعِ لَمْ يَحْنِ رَجُلٌ مِنَّا ظَهْرَهُ حَتَّى يَسْجُدَ ثُمَّ نَسْجُدَ