There are a number of benefits in lowering the gaze:
1 – It is obedience to the command of Allaah, which brings happiness to man in this world and in the next. There is nothing more beneficial to a person in this world and in the next than obeying the commands of his Lord, may He be blessed and exalted, and those who are happy in this world and the next can only attain that happiness by obeying His commands, and those who are doomed in this world and in the next are only doomed because they ignore His commands.
2 – It prevents the poisoned arrows (of the shaytaan), which may lead to his doom, from reaching his heart.
3 – It creates a heart that is devoted to and focused on Allaah. Letting the gaze wander distracts the heart and keeps it far from Allaah. There is nothing more harmful to a person than letting his gaze wander, as it creates alienation between a person and his Lord.
4 – It strengthens the heart and brings it peace, just as letting the gaze wander weakens it and makes it sad.
5 – It brings light to the heart, just as letting the gaze wander brings darkness to it. Hence Allaah mentioned the verse of light immediately after the command to lower the gaze, as He says (interpretation of the meaning):
“Tell the believing men to lower their gaze (from looking at forbidden things), and protect their private parts…”[al-Noor 24:30]
Then straight after that He says (interpretation of the meaning):
“Allaah is the Light of the heavens and the earth. The parable of His Light is as (if there were) a niche and within it a lamp” [al-Noor 24:35]
i.e., the likeness of His light in the heart of His believing slave who obeys His commands and heeds His prohibitions. If the heart is enlightened blessings will come to it from all sides, but if it is darkened, calamity and evil will come to it from all places. Whatever exists of innovation, misguidance, following whims and desires, avoiding true guidance and turning away from the means of happiness and focusing on the means that lead to doom, that will be recognizable by means of the light that is in the heart. If that light is lost then one will left like a blind man stumbling in the darkness.
6 – It generates true insight which can distinguish between truth and falsehood, sincerity and lies. Allaah rewards His slave for his good deeds with something similar and if he gives up something for the sake of Allaah, He will compensate him with something better than it. So if he lowers his gaze and refrains from looking at things that Allaah has forbidden, Allaah will compensate him with enlightenment; he will compensate him for restraining his gaze for the sake of Allaah, and will open to him the doors of knowledge, faith and true insight which he only attained by means of the light in his heart. The opposite of that is the blindness which Allaah attributed to the homosexuals, which is the opposite of insight. Allaah says (interpretation of the meaning):
“Verily, by your life (O Muhammad (peace and blessings of Allaah be upon him), in their wild intoxication, they were wandering blindly” [al-Hijr 15:72]
7 – It creates a heart that is steadfast, brave and strong. Allaah will give him both insight and power and strength, as it says in the report: “The one who goes against his whims and desires, the shaytaan flees from his shadow.”
On the other hand, the one who follows his whims and desires will feel a sense of humiliation, indignity, worthlessness and insignificance, which is the punishment which Allaah has decreed for those who disobey Him as al-Hasan said: “Even if they ride the finest of mounts, the effect of sin will never depart from them. Allaah insists that the one who disobeys Him will be humiliated.”
Allaah, may He be glorified and exalted, has connected strength to obedience to Him, and humiliation to disobedience to Him. Allaah says (interpretation of the meaning):
“But honour, power and glory belong to Allaah, and to His Messenger (Muhammad (peace and blessings of Allaah be upon him), and to the believers” [al-Munaafiqoon 63:8]
“So do not become weak (against your enemy), nor be sad, and you will be superior (in victory) if you are indeed (true) believers”[Aal ‘Imraan 3:139].
Faith is both words and deeds, inward and outward. Allaah says (interpretation of the meaning):
“Whosoever desires honour, power and glory then to Allaah belong all honour, power and glory [and one can get honour, power and glory only by obeying and worshipping Allaah (Alone)]. To Him ascend (all) the goodly words, and the righteous deeds exalt it (i.e. the goodly words are not accepted by Allaah unless and until they are followed by good deeds)”[Faatir 35:10]
i.e., whoever desires power, let him seek it by means of obedience to Allaah and remembrance of Him, by speaking good words and doing good deeds. In Du’aa’ al-Qunoot it says: “he is not humiliated whom You have befriended, nor is he honoured who You take as an enemy”. Whoever obeys Allaah is His friend in as much as he obeys Him, and he will have support and honour from Him commensurate with his obedience towards Him. Whoever disobeys Him is His enemy in as much as he disobeys Him, and he will have humiliation from Him commensurate with his disobedience towards Him.
8 – It blocks the shaytaan from a means of entering his heart, for he may enter with looking, and penetrate the heart faster than the wind blowing through an empty space, and he may present to him the image that he looked at and make it attractive, like an idol to which his heart becomes devoted, then he encourages him and gives him hopes, and fans the flames of desire in his heart, adding the fuel of sin which could not have reached his heart without looking at that image. So his heart becomes inflamed and surrounded with fire on all sides, resulting in infatuation and frustration, and he is in the midst of it like a lamb in the oven. Hence the punishment for those whose desires were fuelled by haraam looking is that in al-Barzakh they are placed in an oven of fire.
9 – It distracts one from thinking of what is in one’s best interests, so his affairs become neglected and he follows his whims and desires and neglects to remember his Lord. Allaah says (interpretation of the meaning):
“and let not your eyes overlook them, desiring the pomp and glitter of the life of the world; and obey not him whose heart We have made heedless of Our remembrance, and who follows his own lusts, and whose affair (deeds) has been lost” [al-Kahf 18:28]
10 – Between the eyes and the heart there is a connection which means that the one is affected by the other, and if one of them becomes good, the other will also become good, and if one becomes corrupt the other will become corrupt. If the heart becomes corrupt the gaze will become corrupt, and if the gaze become corrupt the heart will become corrupt, and similarly if one is sound the other will also be sound.