بسم الله الرحمن الرحيم الحمد لله والصلاة والسلام على رسول الله وعلى آله وصحبه ومن والاه وبعد
Q: What should a Muslim do with regard to the sectarian differences between Muslim parties and groups?
A: A Muslim should adhere to the truth indicated by Allah's Book and the Sunnah of Allah's Messenger (peace be upon him) and deal with others on this basis. A Muslim should love those who adhere to this truth, show enmity with those who fail to have it, and disavow and oppose every party or doctrine that contradicts the truth.
The religion of Allah is integral; it is the right path represented in worshiping Allah (Exalted be He) and following His Messenger Muhammad (peace be upon him).
This is the sound view that every Muslim should adopt; a true Muslim is that who worships Allah (Exalted be He), follows his Shari'ah (divine laws) which He (Exalted be He) revealed to His Prophet Muhammad (peace be upon him), devotes worship to Him Alone, seeks none other than Allah (may He Exalted and Glorified) with worship, shuns every doctrine that lacks these facts or any party that contradicts this belief, and calls people to the truth substantiated by Shar'y (legally accepted) evidence with kindness and the use of useful method in showing the truth.