وَشَرْطُهُ كَوْنُ عَطْفِ الثَّانِيَةِ عَلَى الْأُولَى مَقْبُولًا بِالْوَاوِ
A condition is that joining the second to the first by wāw be acceptable.
A wāw joining two clauses requires some intelligible connection, termed the jāmiʿ. The listener must be able to understand why the two predications are presented as members of one coordinated unit.
The link need not mean identical meanings. It may arise from a common subject, related actions or even opposites that are naturally conceived together. What matters is a plausible conceptual relation that justifies coordination rather than a random juxtaposition.