Sahih Bukhari
Actions while Praying
Volume: 002 / Book Number: 022 / Hadith Number: 327
Narrated Asma':
I went to 'Aisha and she was standing praying and the people, too, were standing (praying). So I said, "What is the matter with the people?" She beckoned with her head towards the sky.
I said, "(Is there) a sign?" She nodded intending to say, "Yes."