Umayyah would openly and publicly revile Rasulullah (sallallahu ‘alaihi wasallam). When he would pass by Rasulullah (sallallahu ‘alaihi wasallam), he would mockingly wink his eyes. Due to this behaviour of his, the following surah was revealed:
وَیۡلٌ لِّکُلِّ ہُمَزَۃٍ لُّمَزَۃِۣ ۙ﴿۱﴾ الَّذِیۡ جَمَعَ مَالًا وَّ عَدَّدَہٗ ۙ﴿۲﴾ یَحۡسَبُ اَنَّ مَالَہٗۤ اَخۡلَدَہٗ ۚ﴿۳﴾ کَلَّا لَیُنۡۢبَذَنَّ فِی الۡحُطَمَۃِ ۫﴿ۖ۴﴾ وَ مَاۤ اَدۡرٰىکَ مَا الۡحُطَمَۃُ ؕ﴿۵﴾ نَارُ اللّٰہِ الۡمُوۡقَدَۃُ ۙ﴿۶﴾ الَّتِیۡ تَطَّلِعُ عَلَی الۡاَفۡـِٕدَۃِ ؕ﴿۷﴾ اِنَّہَا عَلَیۡہِمۡ مُّؤۡصَدَۃٌ ۙ﴿۸﴾ فِیۡ عَمَدٍ مُّمَدَّدَۃٍ ٪﴿۹﴾
Woe unto every backbiter and person who taunts! He who accumulates wealth and repeatedly counts it. Does he think that his wealth will bring him eternity? Never! Verily, he will be hurled into the crushing fire! And do you know what is the crushing fire? It is the kindled fire of Allah Ta‘ala which will leap over the hearts. Indeed, the fire will be sealed over them in extended pillars. (Surah Humazah)
Umayyah bin Khalaf was slain in the Battle of Badr, wither at the hands of Hazrat Khubaib (radhiyallahu ‘anhu) or Hazrat Bilaal (radhiyallahu ‘anhu).
(Extracted from Deeratul Mustafa 1/214-215)