Iqtibās incorporates words from the Qurʾān or hadith into one's prose or poetry without framing them as an explicit formal citation. Taḍmīn incorporates a verse or hemistich from another poet. Both may draw on prior wording, but their sources and modes of presentation differ.
فَصَبْرٌ جَمِيلٌ
So fitting patience is best.
If a poet embeds this familiar Qurʾānic wording within a new composition, the issue is literary quotation. If a speaker explicitly introduces it with “Allah says” and cites scripture as scripture, it is an overt citation, not the ordinary example of this specific literary category.
When a borrowed poetic line is not widely recognizable, indicating its attribution also matters; obscurity does not give a writer licence to present another poet's work as original.