Abu Hurairah (May Allah be pleased with him) reported:
Messenger of Allah (peace be upon him) said, "The believers who show the most perfect Faith are those who have the best behaviour, and the best of you are those who are the best to their wives".
The believer who has excellent behavior attains the highest level of faith. One's wife is the most entitled to one's excellent treatment. In fact, the man who has the best manners is indeed the one who treats his wife best.