Unity and collective effort are fundamental principles in Islam. Allah says:
"And hold firmly to the rope of Allah all together and do not become divided." (Surah Aal-e-Imran 3:103)

He also says:
"There should be a group among you who invite others to what is good, enjoin what is right, and forbid what is wrong." (Surah Aal-e-Imran 3:104)

To achieve any significant goal, working collectively is essential. The Islamic movement, which aims to establish the Deen, cannot succeed without organized effort. Being outside the group leaves one vulnerable, like a lone sheep to a wolf, and the Devil (Shaytan) waits to misguide the isolated. Unity protects us and strengthens the cause of the Deen.