Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "On the Day of Resurrection, the most excellent jihad in the presence of Allah Almighty will be that of those who face the enemy in the front row and do not turn their faces away until they are martyred. These people will dwell in the highest chambers of Paradise. Their Lord looks at them, and when He smiles at a people, no reckoning will be required of them."
Al-Tabarani recorded it in al-Mu'jam al-Awsat through Anbasah bin Sa'id bin Aban, whom al-Daraqutni (may Allah have mercy on him) declared thiqah (trustworthy), as al-Dhahabi reported; no one has declared him weak. The rest of its narrators are the narrators of the Sahih.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الجهاد / 9514