Tafsir of An-Nazi'at 79:19

"And I will guide you to your Lord" means: I will direct you toward the knowledge of Him—Exalted and Majestic is He—so that when you know Him, you will fear Him.

Indeed, fear does not occur except after knowing Him. Allah the Almighty said: "Only those among His servants who have knowledge fear Allah" [Fatir: 28]. He made fear the ultimate goal of guidance because it is the foundation of the entire matter; whoever fears Allah the Almighty will attain every good from Him, and whoever feels secure [from His punishment] will dare to commit every evil. This is in line with the Prophet's (may Allah’s peace and blessings be upon him) saying, as narrated by al-Tirmidhi on the authority of Abu Hurayrah: "Whoever fears [the coming of the night] sets out early, and whoever sets out early reaches the destination."

In the interrogative form [of the preceding verses], there is an unmistakable subtlety in the invitation and an attempt to humble him from his arrogance. This is a detailed application of Allah the Almighty’s statement: "And speak to him with gentle speech, that perhaps he might remember or fear" [Ta-Ha: 44].

The prioritization of purification (tazkiyah) over guidance (hidayah) is because the former is a process of emptying [the soul of corruption], and the fa (the 'f' in fatahda - "then you might fear") in the statement of Allah the Almighty...