so when one of you sees a woman, he should come to his wife
Jabir(may Allah be pleased with him) reported that Allah's Messenger (may the peace and blessings of Allah be upon him) saw a woman, and so he came to his wife, Zainab, as she was tanning a leather and had sexual intercourse with her. He then went to his Companions and told them:
The woman advances and retires in the shape of a devil, so when one of you sees a woman, he should come to his wife, for that will repel what he feels in his heart.
The Prophet (may the peace and blessings of Allah be upon him) gave his companions the good example, and he showed them how to fear Allah, and how to guard against the seditions and to deal with them if the Muslim is tested.
For this purpose, marriage is legislated. It is obligatory for the one who is in a dire need for it, he fears to commit adultery and is able to afford the marriage expenses. It is recommended for the one who is in a need for it is able to afford the marriage expenses but he is not afraid of committing adultery.
That is why Allah ordered men and women on equal basis to lower the gaze and to protect the private parts.
It is better for the man to lower his gaze if he saw a woman than to follow the footsteps of the Satan which he will continue to follow if he followed the first step. Perhaps he may not be able to turn back until he does the last thing the devil wants from him.
Allah has prescribed guidelines for men and women, to prevent them from the free mixing with each other in order to avoid all the forms of sedition, so that the believer remain purified and far away from the deviated lusts and the delusion of Satan. It is clear that these guidelines are prescribed to guard against the doubtful matters and to keep one`s honor blameless.
One of the bad effects of letting the gaze free is that it distracts the soul from the remembrance of Allah, and that it causes the heart to be permanently grieved until it is broken.
Allah will reward the slave is grater better than his deeds; the Most Generous one compensates the slave who lift the prohibited matters with better than that he lift. If the slave restricted his gaze, Allah will grant him an insight and opens to him the doors of knowledge and faith.