رَجَعَ الْمُسَافِرُ. اسْتَقْبَلَهُ أَهْلُهُ بِفَرَحٍ.
The traveler returned. His family welcomed him joyfully.
If the first report naturally prompts “What happened when he returned?”, the second may serve as an answer to an implicit question. That gives a contextual basis for explanatory resumption (istiʾnāf bayānī). But if the speaker is merely narrating two separate events, the specific explanation is not secure.
A careful analysis must state the likely unspoken question and show how the next clause answers it. The mere possibility of some imagined question is not enough.