Refer to point 28 and its accompanying footnote.
The Prophet (sallallaahu alaihi wa sallam) said, Whoever abuses my Companions, upon them is the curse of Allah, the angels and all the people. Reported by at-Tabaraanee from Ibn Abbaas and Ibn Umar. Shaikh Al-Albaanee (rahimahullaah) declared the hadeeth hasan in as-Saheehah (no.2340).
Al-Laalikaaee reportd in as-Sunnah (no.2359) that Imaam Ahmad said, If you see anyone speaking ill of the Companions of the Messenger of Allah (sallallaahu alaihi wa sallam), doubt his Islam.
 The wording as reported by Imaam Ahmad is, Leave my Companions for me. For Him in whose hand is my soul, if you were to spend the like of Uhud or the mountains in gold, you would not reach their actions. Declared saheeh by Shaikh al-Albaanee (rahimahullaah) in Saheehul-Jaami (no.3380).
 We should also hate those who have any ill feelings for any of the Companions since Allah, the Most High, declared that He is pleased with them. Refer to Soorah al-Hashr, Aayaat 8-10, Soorah at-Tawbah, Aayah 100 and Soorah al-Fath, Aayah 18. Indeed, those who attack the Companions are wicked heretics, seeking to destroy Islam, since the whole religion was transmitted to us by the Companions.