So it is as if it were said: What is it that prevents them from establishing between us, while the one who hates does not associate with the one he hates? It was said: Because they do not find what protects them from you. 'If they were to find a refuge' means: something they could resort to, from a fortress, or a mountain, or a people who would protect them from you, or 'caves' in the mountains that could accommodate them. The plural of 'cave' is 'magharah' - a place where one enters. 'Al-ghawr' refers to what is lowered from the land.

And since the caves - which are the openings in the mountains - are spacious and easy to access, it was said: 'or a place of entry' means: a place they could enter with great difficulty and hardship due to its narrowness, or due to an obstacle in their way, or a people who would allow them to enter, even if they dislike them - as indicated by the emphasis: 'If they were to turn back to it' means: they would intensify their direction towards it, turning away from you on their heels. 'And they are galloping' means: their state is like that of an animal that was rushing in obedience to its rider, but then it turned back on its heels, and then it took off in a direction other than intended, with the utmost speed and the greatest desire and urge, not deterred by a pit it might fall into, nor by a calamity, nor by anything.