The conquests during the caliphate of Umar (may Allah be pleased with him)

It is narrated from Abu al-Safar (may Allah have mercy on him) that whenever Sayyiduna Abu Bakr al-Siddiq (may Allah be pleased with him) dispatched (an army of mujahidin) towards Syria, he would take their pledge that they would remain steadfast (on the battlefield) in both situations: "the thrust of the enemy's spears and the epidemic of plague".
Imam Musaddad narrated this athar in his Musnad; there is a break (inqita') in its chain because Abu al-Safar's hearing from Sayyiduna Abu Bakr al-Siddiq (may Allah be pleased with him) is not established.

It is narrated from Dhakwan (may Allah have mercy on him), the freed slave of Sayyidah Aishah (may Allah be pleased with her), that a precious casket was brought to Sayyiduna Umar bin al-Khattab (may Allah be pleased with him). Most of his companions looked at it but could not determine its true value. Then Sayyiduna Umar (may Allah be pleased with him) said: "Do you permit me to send this casket to Sayyidah Aishah (may Allah be pleased with her), because of the immense love the Messenger of Allah (peace and blessings be upon him) had for her?" All agreed and said: "Yes!" So it was brought to Sayyidah Aishah (may Allah be pleased with her), and when she opened it she was told that Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) had sent this gift for her. Then Sayyidah Aishah (may Allah be pleased with her) said: "What doors of the world Ibn al-Khattab has opened for me after the Messenger of Allah (peace and blessings be upon him)!" Then she supplicated to Allah: 'Allahumma la tubqini li-'atiyyati qabil' (O Allah, do not keep me alive (in this world) until I receive next year's stipend).
Imam Abu Ya'la narrated this hadith in his Musnad, and all the narrators in its chain are thiqat (trustworthy) and reliable.