Allah Ta’alah chose the Salaf-e-Saliheen for the preservation of Islam. In every field of Islam, the Salaf-e-Saliheen distinguished the pure untouched teachings of Islam from any foreign unislamic concepts and thus, over the course of 1400 years, Islam remained in its original form. Whether it be the steadfastness of the Companions on the plain of Badr or the great heroism shown on the mountains of Uhud, be it the severe torture endured by Imam Abu Hanifah (rahimahullah) and Imam Ahmad bin Hanbal (rahimahullah) or the long journeys Imam Bukhari (rahimahullah) undertook in his thirst for knowledge, be it Shaykhul-Islam Ibn Taymiyah's (rahimahullah) defiance of the tyrannical Tartar forces or Imam Ghazali's (rahimahullah) challenging the corrupt philosophical ideologies of his time; in every age and in every field, our pious predecessors fulfilled the responsibility of preserving Islam and Allah the Almighty has spoken the truth:
"O ye who believe! If ye help (the cause) of Allah, He will help you, and plant your feet firmly."
(Surah Muhammad: 7)

Role of Salaf-e-Saliheen in Islam : Never Underestimate their Reasoning - Maulana Ishaq