Tirmidhi

Explanation:
1:
It is at a distance of four miles from Madinah.

2:
In some narrations, it is mentioned that his bravery and courage were so renowned that the Companions became pleased upon seeing him. Then he himself clarified that he was participating solely out of the desire to obtain a share of the war booty (maal-e-ghanīmah). When he explicitly stated that he had not embraced faith, the Prophet (sallallahu alayhi wa sallam) refused to accept his assistance. Later, he professed faith and, with the Prophet’s (sallallahu alayhi wa sallam) permission, participated in the battle.

Here, the question arises again: Is it permissible to seek help from a disbeliever or not? One group holds the view that it is permissible to seek help, while others opine that help may be sought in times of necessity, as the Prophet (sallallahu alayhi wa sallam) accepted assistance in the form of weapons from Safwan bin Umayyah and others during the Battle of Hunayn, and similarly, help was taken from the Jews of Banu Qaynuqa. In any case, there is allowance to seek both weaponry and manpower assistance in situations of severe need and necessity.

Hadith Commentary:
Benefits and Issues:
According to the four Imams, if a non-Muslim abides by the commands and instructions of the Muslim leader and holds a good opinion regarding the Muslims, and if there is a need to seek his help due to his military expertise and he himself expresses the desire (to participate), then it is permissible to take help from him. However, he will not receive a fixed share from the war booty (ghanimah); rather, he may be given something as a gift or reward.

And if there is no need to take help from him, or there is a risk that he may become a cause of mischief and corruption, then help will not be sought from him. And here, the reason for your (sallallahu alayhi wa sallam) refusal was that, through the insight of Prophethood, you perceived that he would become a Muslim, or that this was the first battle and you did not feel the need for his help, because you had set out from Madinah to attack a caravan, and at that time there was no knowledge of an impending confrontation with an army.

Benefits and Issues:
When assistance is not taken from the polytheists, then their share in the spoils of war (ghanimah) is meaningless.
And the fundamental rule and principle of Islamic governance is precisely that assistance should not be sought from the polytheists.
However, depending on circumstances and interests, if there is a situation of necessity, then assistance may be taken against the disbelievers.
Not against the Muslims, as in the journey of migration (Hijrah), when the Messenger of Allah (sallallahu alayhi wa sallam) and Abu Bakr as-Siddiq (radi Allahu anhu) completed their journey under the guidance of Abdullah bin Uraiqit al-Laithi.
He was a polytheist, but he was trustworthy.
If such a situation arises, then reward or the like may be given.
And Allah knows best. See:
(Nayl al-Awtar, Chapter: What has been reported regarding seeking assistance from the polytheists: 7/254)

Benefits and Issues:
(1)
A Muslim engages in jihad to defend his creed. The defense of the land of a Muslim country is also important for this reason, as it is a part of defending the religion. Since a polytheist does not accept this creed, he cannot fight sincerely for its defense.

(2)
A non-Muslim is either an open enemy of the Muslims or is under the protection of the Muslims. The first type of polytheist (harbi) cannot be included in the Islamic army because the Islamic army fights against him. The second type of polytheist (dhimmi) is under the protection of the Muslims. And one who is protected by the Muslims cannot be required to protect and defend the Muslims.