Question: Is it allowed for one to pray behind another who smokes marijuana or has so within the past 40 days? How do we respond to such actions?
Answer:
In the Name of Allah, the Most Merciful and Compassionate,
Short Answer
Your prayers behind a person who smokes marijuana are valid. It is better for you to pray in the congregation behind them than to pray alone. The following details aim to shed more light on the issue:
The Ruling of Smoking Marijuana
Smoking marijuana is strictly prohibited. [Nahlawi, al-Durar al-Mubaha]
Acceptance of Prayer Performed Intoxicated
There are a few narrations regarding prayer not being accepted for 40 days if one takes intoxicants. The Messenger of Allah (Allah bless him and give him peace) “Whoever drinks wine, his prayer is not accepted from him for 40 days. If he repents, Allah forgives him…” [Tirmidhi]
Acceptance in this verse refers to reward not validity. One is not obliged to repeat their prayer behind such a person. The prayer is valid, and the follower is not culpable for the wrongs of the Imam. [Mubarakpuri, Tuhfa al-Ahwadhi citing Mulla ‘Ali Qari and al-Nawawi]
If one is faced with a choice between praying alone and praying behind a person who smokes marijuana, it is better for them to pray in a congregation behind such an imam. They will still achieve the reward of the congregation. However, the reward will not equate to the reward of praying behind a righteous person. [Ibn ‘Abidin, Radd al-Muhtar]
Note that the above assumes that the imam performs the prayer properly. If they are so intoxicated that the prayer is not performed properly, one must not pray behind them.
Sincere Concern
The Believer’s response to the sins of others must be a response of sincere concern. Fudayl bin ‘Iyad (Allah have mercy on him) said, “The Believer veils, admonishes, and gives sincere counsel. The corrupt person exposes, finds fault, and reveals secrets.” [Abu Nu’aym, Hilya al-Awliya]
Summary
If you have the choice to pray elsewhere, and doing so is not unduly difficult, take that option when possible. If not, pray in the congregation. When the time is appropriate and you feel the benefit is likely, advise them to leave their sinful habit. If they do not heed your advice, pray for them and treat them in a dignified matter.
See the following link for more details:
Smoking marijuana and the importance of keeping good company:
Hope this helps
Allah knows best
[Shaykh] Yusuf Weltch
Checked and Approved by Shaykh Faraz Rabbani