And We had sent Nuh to his people so he said, “O my people! serve (worship) Allah, there is no god for you other than Him. Will you not then guard (against the evil of worshipping others)?” (Al Quran, Surah Al Muminun, Chapter 23: Verse 23)
The above verse should be read in context of the following verses:
23-24: So the leaders of those who did not believe from among his people said, “He is no more than a man like yourselves, he intends to achieve superiority over you, and had Allah willed He would have sent down angels, We have not heard this among our ancient forefathers.
23-25: He is nothing but a man who is possessed by jinn, so bear with him till (some) time.”
23-26: He said, “My Fosterer! help me because they deny me.”
23-27: So We communicated to him, “Make the ship before Our eyes and (according to) Our communication. Then when Our commandment comes and the water gushes forth from (the reservoir in) the valley, make each pair (consisting) of two, to enter the (ship) along with your people, except him among them against whom the word has already gone forth, and do not speak to me regarding those who are unjust, they will certainly be drowned.
23-28: Then when you are balanced on the ship, you and those with you, then say: “Praise is due only for Allah Who delivered us from the unjust people.”
23-29: And say, “My Fosterer! make me alight a blessed alighting and You are the Best of those who cause to alight.”
23-30: There are certainly signs in that, and We are ever testing (people).
Summarized Commentary:
Nuuh (PBH): name of a prophet who was sent to his people to warn them that they should worship only Allah (SWT) fearing Him and they should obey him. He tried all methods of inviting his people towards Allah (SWT) but they disobeyed him and got involved in idol worship, therefore those who disobeyed him were drowned (Chapter 71: Verses 1-28). Earlier Nuuh (PBH) was asked to build a ship in accordance with the communications of Allah (SWT) (Chapter 11: Verse 37). This was probably the first invention of mankind but under Divine guidance. Are all other inventions too under Divine guidance? When the water gushed forth Nuuh (PBH) was asked to take in his ship two of each pair, his people and the believers Chapter 11: Verse 40) after the water receded the ship rested on Mount Judi (Chapter 11: Verse 44). The son of Nuuh (PBH) was not saved from drowning (Chapter 11: Verses 42-46) and Nuuh’s (PBH) wife did not believe (Chapter 66: Verse 10). This shows that belief and consequent deeds have nothing to do with relationship. Nuuh (PBH) lived for 950 years (Chapter 29: Verse 14).