Tafsir of At-Tawbah 9:56

{They swear by Allah that they are indeed among you} Meaning: Among the body of the Muslims.

{But they are afraid} Meaning: They fear being killed and what is done to the polytheists, so they feign Islam out of taqiyyah (precautionary dissimulation).

{A place of refuge} Meaning: A place they can resort to, fortifying themselves within it, such as a mountain peak, a fortress, or an island.

{Or caves} Meaning: Or caverns. It is also recited with a damma on the mim (mugharat), derived from aghara al-rajul and ghara, meaning when one enters a deep depression (ghawr). It is also said to be the transitive form of ghara, meaning places where they can hide their persons. It is also permissible that it comes from "the fox aghara (rushed)," meaning places of escape.

{Or a tunnel} Meaning: Or a burrow into which they can slip and hide, derived from the form mufta'al from al-dukhul (entering). It is also recited as madkhalan (from dakhala) and mudkhalan (from adkhala), meaning a place into which they insert themselves. Ubayy ibn Ka'b (may Allah be pleased with him) recited it as mutadakhala. It is also recited: law law ilayhi la-ltaja'u ilayhi.

{They rush headlong} Meaning: They hasten with a speed that nothing can turn back. It is derived from the "headstrong horse" (al-faras al-jamuh), which is the one that, once it charges, the bridle cannot restrain. Anas (may Allah be pleased with him) recited it as yajmuzun. When asked about it, he said: "They mean the same thing: yajmahun, yajmuzun, and yashtuddun (they run fast)."

{And among them are those who criticize you concerning the charities. If they are given from them, they are pleased; but if they are not given from them, at once they become angry.}