According to Islamic teachings and experience of others, for decreasing concupiscence and preventing Jinabat, please refer to the following recommendations:
1. Avoid dreaming and try to make yourself busy with good things such as reading books (non-sexual ones), heavy exercise, etc. Moreover, remember that idleness can lead you to anything.
2. If possible, try not to be alone anywhere.
3. Avoid watching any type of pictures and movies sexual in nature.
4. Fasting can be quite helpful in controlling your internal desires and strengthening your will.
5. If you cannot fast, do not eat a lot or at least do not over load your stomach when you want to sleep.
6. Read some books before going to sleep at night and never sleep on your front.[1]
7. If possible, urinate before going to sleep in order to empty your bladder and use cold water for washing in water closet.
8. Do not touch your private parts of your body when it is not necessary.
9. Remember Allah (SWT) all the time especially at the time of sleeping and recite some verses of the Holy Quran at this time.
10. Try not to think about lustful desires at the time of sleeping.
11. Muawiya ibn Ammar narrated from Imam Sadiq (a.s) that His Excellency said: "read this following Dua if you are afraid of becoming Jonob during sleep"

"اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الِاحْتِلَامِ وَ مِنْ سُوءِ الْأَحْلَامِ وَ مِنْ أَنْ يَتَلَاعَبَ بِيَ الشَّيْطَانُ فِي الْيَقَظَةِ وَ الْمَنَام‏"[2]

"O Allah, I take refuge in You from Jinabat and bad dreams and also from the temptation of Satan all the times"

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