“Baddalū niʿmata Allāhi kufran”
“They exchanged God’s blessing for ingratitude.” (Ibrāhīm 14:28, excerpt)
The expression means that gratitude should have been shown for a divine favor, but unbelief or ingratitude was chosen in its place. An explanatory reconstruction makes the implicit comparison with the act of gratitude explicit.
The statement does not describe physical objects being exchanged. It addresses a moral response to blessing.
A brief verbal construction can carry an entire ethical contrast: what ought to have followed from a favor, and the corrupt reaction that actually replaced it. Explanation should reveal that contrast without dulling the original terseness.