وَنَادَىٰ نُوحٌ رَّبَّهُ فَقَالَ رَبِّ إِنَّ ابْنِي مِنْ أَهْلِي وَإِنَّ وَعْدَكَ الْحَقُّ وَأَنتَ أَحْكَمُ الْحَاكِمِينَ (45)
(11:45) And Noah called out to his Lord, saying: 'My Lord! My son is of my family. Surely Your promise is true, *47 and You are the greatest of those who judge. *48
*47). Noah (peace be on him) reminds God of His promise to spare his family. Since his son was quite obviously part of his family. Noah requests of God that he be spared.
*48). Noah (peace be on him) acknowledges that God's judgement is final; that it is one against which there can be no appeal. Moreover, God's judgement is also based on absolute knowledge and perfect justice.