Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) says: As long as you are in the state of prayer, you are knocking at the door of the King, and whoever keeps knocking at the door of the King abundantly, that door is eventually opened for him.
This narration was recorded by Imam al-Tabarani in al-Mu'jam al-Kabir; its narrators are the narrators of the "Sahih".
Imam al-Tabarani also recorded this narration on the authority of Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him): "The example of one who regularly performs (voluntary) prayer is like that of a person who keeps knocking at a door; whoever keeps knocking regularly, that (door) is opened for him."
Imam al-Sha'bi says: Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) did not perform the forenoon (Duha) prayer. He used to pray between Zuhr and Asr, and he would perform long (voluntary) prayer at night.
This narration was recorded by Imam al-Tabarani in al-Mu'jam al-Kabir; its chain contains a narrator whose name has not been given.
Ali bin Abi Hamlah and Imam al-Awza'i say: Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) used to perform one thousand prostrations every day (perhaps this means that he used to perform one thousand rak'ahs).
This narration was recorded by Imam al-Tabarani in al-Mu'jam al-Kabir, and its chain is munqati' (broken).