Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: The Prophet (peace and blessings be upon him) was walking along with the people towards Baqi' al-Gharqad. Then he turned towards them and said: "Set off in the name of Allah. O Allah, help them." The narrator says: That is, the Prophet (peace and blessings be upon him) said this for the men whom he sent to Ka'b bin al-Ashraf.
Ahmad and al-Bazzar recorded it; however, he (al-Bazzar) recorded these words: "When the Prophet (peace and blessings be upon him) sent Sayyiduna Muhammad bin Maslamah (may Allah be pleased with him) and his companions to Ka'b bin al-Ashraf so that they might kill him (at that time this incident took place)"; the rest of the report is as before.
Al-Tabarani recorded it and added these words: "Then the Prophet (peace and blessings be upon him) returned to his house." The chain of this report contains Ibn Ishaq, and he is a mudallis; the rest of the narrators of this report are the narrators of the Sahih.
Hadith Takhrij«اخرجه البزار فى المسند (1801 و 1802) اخرجه الطبراني فى المعجم الكبير (11554) اخرجه احمد فى المسند 2391 ، أخرجه مسند أحمد برقم: 2387، وأخرجه المستدرك على الصحيحين برقم: 2525»