forsake their beds…until he reached the words, “…for what they used to do.” (32:17)

He then said, “Shall I not tell you of the head of the matter, its pillar, and its highest peak?” I replied, “Yes, O Messenger of Allah.” He said, “The head of the matter is Islam, its pillar is the prayer, and its highest peak is jihad.” He went on, “Shall I not inform you of what keeps all of that in check?” I said, “Yes, O Messenger of Allah.” So he took hold of his tongue and said, “Restrain this.” I asked, “O Messenger of Allah, are we really to be held accountable for what we say?” He replied, “May your mother be bereaved of you! Are people thrown on their faces into the Fire for anything other than the harvest of their tongues?” Narrated by al-Tirmidhi, who said: “A ḥasan ṣaḥīḥ (sound and authentic) hadith,” and its detailed explanation has already been given.

[Explanation]
This is one of the reports the author—may Allah have mercy on him—cites, all of which warn against the tongue, its evils, and its pitfalls. A person may utter a single word that incurs Allah’s anger, giving it no thought and never imagining it would reach so far; yet because of that word Allah records His wrath against him until the day he meets Him. Every one of these narrations carries the same warning about the tongue and its misfortunes. Hence it is said: “Guard your tongue lest you speak and be afflicted, for calamity is tethered to speech.”

Many people unknowingly pray harm upon themselves: upon their children, their wealth, their friends, their relatives—without realizing it. Such supplication may coincide with an open gate of acceptance, and the invocation comes down upon them.