Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) narrates this saying of the Prophet (peace and blessings be upon him): "I am the leader of the messengers, and I do not say this by way of pride; I am the one who seals the line of the prophets, and I do not say this by way of pride; and I am the first to intercede and the first person whose intercession will be accepted, and I do not say this by way of pride."
Al-Tabarani recorded it in al-Mu'jam al-Awsat; its chain contains a narrator, Salih bin Ata bin Khabbab, and I do not know him; the rest of the narrators of this narration are thiqat (trustworthy).