He might be a Bedouin (not knowing correctly the rituals of Hajj and, therefore, pronouncing Talbia at this stage), whereupon Abdullah said: Hive the people forgotten (this Sunnah of the Holy Prophet) or have they gone astray? I heard him, upon whom Sibrah al-Baqara was revealed, pronouncing Talbiya at the very place.
Sahih Muslim Book 15, Hadith 298