أَنْ يُنْتَزَعَ مِنْ أَمْرٍ ذِي صِفَةٍ أَمْرٌ آخَرُ مِثْلُهُ فِيهَا
To extract, from something possessing a quality, another thing resembling it in that quality.
Dhī ṣifah denotes the first bearer. Amr ākhar denotes the counterpart imagined as extracted; mithluhu fīhā limits the likeness to the relevant characteristic, not complete identity in every respect.
Extraction is figurative rather than physical. It establishes a heightened impression that the characteristic is exceptionally established or complete in the original bearer.