Chapter 25 On helping those who ask something by Allah, the almighty and glorious
Jabir – and in another text, Ibn Umar – narrated that the messenger of Allah (PBUH) said: ''If someone seeks refuge and protection. If someone asks something by Allah, give him what he asks for. If someone calls you, respond to his call, if someone does you a favour, reward him. If you have nothing to reward him with, pay for him until you see that you have offered him an adequate reward.
(Related by Abu Da'ud, an-Nasai, and Ibn Habban)
The prohibition of asking for the sake of Allah
Rafi' reported that the messenger of Allah (PBUH) said: ''According is he who asks 'for the sake of Allah' (li wajh Allah); and accursed is he who is asked for the sake of Allah' and turns away the one who asked''.
(Related by at-Tabarani)