It was narrated from Ibn 'Umar that the Prophet ﷺ said:

"The month is like this," and (one of the narrators) Shubah did the same gesture as Jabalah had done, copying, Ibn 'Umar: "It is twenty-nine, as he gestured twice with all fingers of both hands, and putting down one of his fingers the third time."

أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ جَبَلَةَ بْنِ سُحَيْمٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ ﷺ قَالَ " الشَّهْرُ هَكَذَا " . وَوَصَفَ شُعْبَةُ عَنْ صِفَةِ جَبَلَةَ عَنْ صِفَةِ ابْنِ عُمَرَ أَنَّهُ تِسْعٌ وَعِشْرُونَ فِيمَا حَكَى مِنْ صَنِيعِهِ مَرَّتَيْنِ بِأَصَابِعِ يَدَيْهِ وَنَقَصَ فِي الثَّالِثَةِ إِصْبَعًا مِنْ أَصَابِعِ يَدَيْهِ .