Why is wāw appropriate between “naẓẓim aʿmālaka” and “iḥfaẓ waʿdaka”?

Supplementary Practice 8: Rhetorical Analysis of Five Connected Passages

• It links two independent but related practical directives
• The second directive is only verbal emphasis of the first
• The second imperative answers an implied question raised by the first
• The directives have no relevant relation and wāw merely decorates them