Unity can be achieved only through the Imamat of the Ahle Bait (peace be upon them)

Hazrat Zahra (peace be upon her) in her historical sermon said:

وَ طَاعَتَنَا نِظَاماً لِلْمِلَّةِ وَ إِمَامَتَنَا أَمَاناً لِلْفُرْقَة

“…our obedience is the system for religion and our Imamat is a security from disunity…”

References:

1.    Balaaghaat al-Nisaa, p. 28

2.    Al-Ehtejaaj, vol. 1, p. 99,

3.    Behaar al-Anwaar, vol. 29, p. 223 and 241