"And among the bedouins are those who believe in Allah and the Last Day and take what they spend as means of nearness to Allah," meaning: they seek to draw closer to Allah, the Mighty and Majestic, through it, "and as prayers of the Messenger," meaning: and they also take the prayers of the Messenger as a means of nearness to Allah. The prayers of the Messenger are his seeking forgiveness and his supplication for them.
Surat At-Tawbah from verse (100) to verse (101).