The Four Trials in Jihad
The obvious question is: With whom is the talibul 'ilm making jihad?
The answer is: With his nafs.
The mufassirin (authentic commentators of the Quran Sharif) have written lengthy commentaries on this hadith sharif. You are advised to read them.
Let us summarize their findings:
What are the trials facing the mujahidin?
One: I'la'e Deen, also called I'la'e Kalimatullah-to uphold the Deen (or Kalimah of Allah Ta'ala). Jihad is not territorial gain and aggrandizement. Jihad is for the sake of Deen-the purpose is to enable those who have the Deen to practise Deen properly by removing the obstacles that others had placed in their path, also, to stop the torment that others are inflicting on them. This is the first point in jihad-I'la'e Deen.