It was narrated that 'Abdullah said: "The Messenger of Allah said to us: 'O young men, whoever among you can afford it, let him get married, for it is more effective in lowering the gaze and guarding chastity, and whoever cannot then he should fast, for it will be a restraint (wija') for him.'" (Using translation from Nasāʾī 3209)   

عَبْدُ اللَّهِ كُنَّا مَعَ رَسُولِ اللَّهِ ﷺ شَبَابًا لَيْسَ لَنَا شَيْءٌ فَقَالَ «يَا مَعْشَرَ الشَّبَابِ مَنِ اسْتَطَاعَ مِنْكُمُ الْبَاءَةَ فَلْيَتَزَوَّجْ فَإِنَّهُ أَغَضُّ لِلْبَصَرِ وَأَحْصَنُ لِلْفَرْجِ وَمَنْ لَمْ يَسْتَطِعْ فَعَلَيْهِ بِالصَّوْمِ فَإِنَّ الصَّوْمَ لَهُ وِجَاءٌ»  

[Machine] Do you have a young virgin girl who reminds you of Abu Abdurrahman? So he said, "If you say that, then I have heard the Messenger of Allah ﷺ say, 'O youth, whoever among you is able to marry, let him do so, for it is more effective in guarding the gaze and preserving chastity. And whoever is not able, then let him fast, for it will be a shield for him.'"  

لَهُ أَبَا عَبْدِ الرَّحْمَنِ هَلْ لَكَ فِي جَارِيَةٍ بِكْرٍ تُذَكِّرُكَ؟ فَقَالَ لَئِنْ قُلْتَ ذَاكَ فَقَدْ سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ «يَا مَعْشَرَ الشَّبَابِ مَنِ اسْتَطَاعَ مِنْكُمُ الْبَاءَةَ فَلْيَتَزَوَّجْ فَإِنَّهُ أَغَضُّ لِلْبَصَرِ وَأَحْصَنُ لِلْفَرْجِ وَمَنْ لَمْ يَسْتَطِعْ فَلْيَصُمْ فَإِنَّ الصَّوْمَ لَهُ وِجَاءٌ»