إِن نَّشَأْ نُنَزِّلْ عَلَيْهِم مِّن السَّمَاء آيَةً فَظَلَّتْ أَعْنَاقُهُمْ لَهَا خَاضِعِينَ
“If We will, We can send down on them from the heavens a sign to which they would bend their necks in humility”
Omar bin Hanzala said, I heard Imam Sadiq (as) say, “There are five signs before the rising of the Qaem (as) the call from the heavens, the (rising of) Sufyani, the collapsing of the earth (in Baydaa), the killing of Nafs-e-Zakiyyah (the purified soul), and the (rising of) Yamaani.”
I (Omar bin Hanzala) asked, May I sacrifice my life for you. If someone from your family rises before we see these signs, should we rise with him?
No, Imam (as) replied.
The next day (I went back to the Imam (as)) and asked him, Does the following verse refer to the call from the heavens, “If we will, We can send down on them from the heavens a sign to which they would bend their necks in humility”
Imam (as) replied, When (this verse applies), the necks of the enemies of Allah will be bent “in humility” (Al Kafi volume 8 page 310)
Imam Sadiq (as) explained the above verse by saying, The verse refers to the call which will announce the name of the Qaem (as) from the heavens, and those whose necks will be bent “in humility” are the Bani Umayyah. (Tafseer Al Qummi volume 2 page 118)