How does «إِنَّ الْبَاطِلَ كَانَ زَهُوقًا» relate to «وَزَهَقَ الْبَاطِلُ»?

Supplementary Practice 1: Applied Analysis of Faṣl, Waṣl, Ījāz and Iṭnāb

• It makes the clauses unrelated
• It reinforces the vanishing of falsehood through a broader independent assertion
• It is a circumstantial connector
• It turns the first into a question