Translation:

25. They are the ones who denied revelation and hindered you from the Sacred Mosque and the sacrificial animals detained from reaching their place of sacrifice. Had there not been believing men and believing women whom ye did not know that ye were trampling down and on whose account a crime would have accrued to you without (your) knowledge. (Allah would have allowed you to force your way but He held back your hands) that He may admit to His mercy whom He will. If they had been apart We should certainly have punished the Unbelievers among them with a grievous punishment.

Notes (Tafseer)

4903. The Muslims from Madinah had brought the animals for sacrifice with them, and had put on the Ihram or pilgrim's garb (see n. 217 to ii. 197), but they were not only prevented from entering Makkah, but were also prevented from sending the sacrificial animals to the place of sacrifice in Makkah, as they could have done under ii. 196. The sacrifice was therefore actually offered at Hudaibiya.

4904. There were at the time in Makkah believing Muslims, men and women, and the faith of some of them was unknown to their brethren from Madinah. Had a fight taken place in Makkah, even though the Muslims had been successful, they would unwittingly have killed some of these unknown Muslims, and thus would unwittingly have been guilty of shedding Muslim blood. This was prevented by the Treaty.

4905. Allah works according to His wise and holy Will and Plan, and not according to what seems to us, in the excitement of human life, to be the obvious course of things. By preventing a fight He saved many valuable lives, not only of Muslims but also of some who became Muslims afterwards and served Islam. He grants His Mercy on far higher standards than man in his limited horizon can see.

4906. If the party from Madinah could have distinguished Muslims from non-Muslims among the Makkans, they might have been allowed to enter and punish the pagan Quraish for their inordinate vanity and gross breach of the unwritten law of the land. But in the actual circumstances the best solution was the Treaty of Hudaibiya.