Al-Kahf 18:79
أَمَّا السَّفِينَةُ فَكَانَتْ لِمَسَاكِينَ يَعْمَلُونَ فِي الْبَحْرِ فَأَرَدتُّ أَنْ أَعِيبَهَا وَكَانَ وَرَاءَهُم مَّلِكٌ يَأْخُذُ كُلَّ سَفِينَةٍ غَصْبًا ٧٩
Amma alssafeenatu fakanat limasakeena yaAAmaloona fee albahri faaradtu an aAAeebaha wakana waraahum malikun yakhuthu kulla safeenatin ghasban
As for the ship, it belonged to certain poor men, who toiled upon the sea; and I desired to damage it, for behind them there was a king who was seizing every ship by brutal force. (18:79)
Interpretations of why the Ship was damaged
This is an explanation of what Musa found so hard to understand, and the appearence of which he condemed. Allah showed Al-Khidr the hidden reasons, so he said, "I damaged the ship to make it faulty, because they used to pass by a king who was one of the oppressors, who
يَأْخُذُ كُلَّ سَفِينَةٍ
(seized every boat), i.e., every good, sound boat
غَصْباً
(by force.) `So I wanted to prevent him from taking this boat by making it appear faulty, so that its poor owners who had nothing else could benefit from it.' It was also said that they were orphans.