Reference: Fataawa Noor ‘alad-Darb – Question No.6322, Page 163, Volume 12
Question: Has [anything been] reported from the Prophet ﷺ that he would raise his hands in supplication after the obligatory prayer?
Response: Nothing has been reported from the Prophet ﷺ that he would raise his hands in supplication after the obligatory prayer, and nor after the voluntary prayer either. Rather, the Prophet ﷺ instructed his ummah that their supplication should be made [within the prayer] – before [ending with] the tasleem. Just as it occurs in the hadeeth of ‘Abdullaah ibn Mas’ood when the Prophet ﷺ taught him the tashahhud and said:
So whoever wishes to supplicate to Allaah عز و جل, then let him supplicate to Allaah before the tasleem, during his moment of intimate discourse with Allaah عز و جل, and because he has reached the point at which the Prophet ﷺ instructed [his ummah to supplicate to Allaah].
And because of this, to delay the supplication until after the tasleem is in opposition to what the Prophet ﷺ instructed, as well as the correct viewpoint, because the correct viewpoint requires the supplication to be during the moment of intimate discourse with Allaah عز و جل – before completing the prayer with the tasleem. And this is more preferable than to delay the supplication until after the moment of intimate discourse with Allaah [has passed], and when he has finished his prayer.
Footnote:
[1] Transmitted by al-Bukhaaree and Muslim