It is stated by sayyidina Ibn Abbas RA ,”If both parents of a muslim are alive and he begins the morning treating them both kindly then Allah swt opens for him 2 doors of paradise. But, if one of them is alive (and he nehaves kindly with the surving parent) the Allah swt opens for him one door of paradise. And, if he displeases them then Allah swt will not be pleased with him until he makes them happy.” Someone asked, “If they oopressive (then what)?” ibn Abbas said, “Even if they are oppressive.”
This hadith emphatically relates the merits of service, obedience and kind treatment to parents. If both parents of a muslim are alive and he gives them respect,serves them obeys them then Allah swt opens 2 gates of paradise for him. However, if only one of the parents is alive and he is respectful, loving and caring to the surviving parent then, because of his pious deed, one gate will be opened for him. In some way the hadith is very explicit in describing the plight of one who is undutiful to his parents. It cautions very clearly that if anyone displeases his parents then he earns the displeasure of Allah swt and does not regain it until he makes amends and pleases his parents.
The concluding portion states that if the parents are oppressive and hard on their child even thendisobedience and hurting them will open the doors of hell for him. But, this does not imply that parents are permitted to be cruel to their offspring. If parents abuse their children then they will face punishment for that and they will be made to pay for their misconduct.
The offspring must realise their own responsibilities and if parents do not fulfil their obligations it is their lookout, not their offspring’s. In fact, this is great advice and useful instruction to live a collective life. Everyone must pay attention to his own responsibilities and not worry how other people treat them (although this is easier said then done). If everyone, young and old is mindful of this advice then inshallah life will be peaceful and allah swt alone enables.
Source: Manners in islam – Abu Abdullah Muhammad bin islamil Bukhari