This is a ḥasan ṣaḥīḥ ḥadīth.

25 – Chapter on the Reward of the Martyr (1)

1756 – ʿAbd Allāh ibn ʿAbd al-Raḥmān narrated to us, Nuʿaym ibn Ḥammād informed us, Baqiyyah ibn al-Walīd narrated to us, from Baḥīr ibn Saʿd, from Khālid ibn Maʿdān, from al-Miqdām ibn Maʿdī Karib, who said: The Messenger of Allāh, peace and blessings be upon him, said: "The martyr has six qualities with Allāh: he is forgiven upon the first gush of blood, he is shown his seat in Paradise, he is protected from the punishment of the grave, he is secure from the Greatest Terror, a crown of dignity is placed upon his head—a single ruby of which is better than the world and all that is in it—he is married to seventy-two wives of the ḥūr al-ʿīn, and his intercession is accepted for seventy of his relatives." (2)

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(1) The title of this chapter is from the printed edition, from the copy of al-Ḥāfiẓ al-ʿIrāqī, and from the margin of (ẓ), but al-ʿIrāqī crossed over it, and in our manuscript sources the chapter heading appears without a title.

(2) Ṣaḥīḥ by virtue of corroborating evidence, apart from the mention of the number of ḥūr al-ʿīn; ḥasan as narrated from al-Miqdām ibn Maʿdī Karib. And Baqiyyah—even though he was a mudallis who practiced tadlīs al-taswiyah and did not explicitly state that he heard it directly—was followed in this by Ismāʿīl ibn ʿAyyāsh al-Ḥimṣī, who is ṣadūq in his narration from the people of his own town, and Baḥīr ibn Saʿd was Ḥimṣī; thus the ḥadīth is ḥasan.
It was also recorded by Ibn Mājah (2799), and it is in al-Musnad (17182).
It is corroborated by the ḥadīth of Qays al-Judhāmī, recorded by Aḥmad (17783), via the chain of ʿAbd al-Raḥmān ibn Thābit ibn Thawbān, from his father, from Makḥūl, from Kathīr ibn Murrah, from Qays al-Judhāmī, with similar wording—without mentioning the number of ḥūr al-ʿīn and without mentioning the intercession—and its chain is ḥasan. However, Abū Nuʿaym al-Aṣbahānī recorded this ḥadīth in Maʿrifat al-Ṣaḥābah, 2/folio 150/a, via the chain of Ibn Thawbān, then said: And Zayd ibn Wāqid narrated it, from Kathīr; Muḥammad ibn Muḥammad narrated it to us =