«عَرَضْتُ خَبِيئَتِي لِلِاخْتِبَارِ»
I have presented my hidden store for testing.
Khabīʾah refers to something concealed or stored. Here it depicts the stranger's poetic gifts, not physical contents being removed from a bag. The connected image of a ḥaqībah (“bag” or store) extends the same metaphor.
Ikhtibār / iʿtibār sound similar but are not synonyms: one is a test, the other careful consideration or evaluation. The paired terms distinguish performance from the judgement made after witnessing it.