To put it into context, we first look at the preceding verses to verse 30 – (Quran 74:21 to 29)
“He looked * He frowned and whined * Then he turned away arrogantly * He said, “This is but clever magic! * This is human made * I will commit him to retribution * What retribution! * Thorough and comprehensive * Obvious to all people.”
Then the verse “Over it is 19″ (74:30)
The 31st verse of the same Surah informs us about the functions of number 19 “God thus sends astray whomever He wills, and guides whomever He wills.” (74:31) – 19 is the only number in the Quran whose functions are commented upon.
A Simple English Version of the Quran – Translated by MAS Abdel Haleem