Opening the prayer with glorification, declaration of faith, praise, magnification, and seeking forgiveness ten times: The Prophet (peace be upon him) said: 'O Umm Rafi'! When you stand for prayer, glorify Allah ten times, declare His Oneness ten times, praise Him ten times, magnify Him ten times, and seek His forgiveness ten times, for when you glorify ten times, He says: This is for Me, and when you declare His Oneness, He says: This is for Me, and when you praise, He says: This is for Me, and when you magnify, He says: This is for Me, and when you seek forgiveness, He says: I have forgiven you.' This supplication is said at the beginning of the prayer. The scholar mentioned in his narration of the hadith: And from Ibn Mundhir, with a correct chain of narration from Hisham ibn Sa'd from Zaid ibn Aslam from Abdullah ibn Wahb from Umm Rafi' who said: O Messenger of Allah, tell me of an action with which I can open my prayer, and he mentioned the hadith. He then concluded the narration by saying: It has been confirmed from his actions (peace be upon him) that the remembrance mentioned in the hadith is in prayer, which has also been reported through various chains from Aisha who said: 'When he (peace be upon him) stood at night, he would open his prayer: he would magnify ten times, praise ten times, glorify ten times, declare His Oneness ten times, and seek forgiveness ten times'... the hadith, narrated by Abu Dawood and others, and it is included in the authentic Abu Dawood (742) and 'The Description of Prayer.' Is this opening supplication for obligatory prayers or voluntary ones?