May the peace, mercy and blessing of Allah be upon you,

There is a practicing brother who we consider to be good – and Allah knows best – he stands in prayer at night and fasts Mondays and Thursdays, but he does not attend the daily congregational prayers, saying that he does not find khushoo` (humility and concentration) when praying in a group. Is that a legitimate reason for leaving the congregational prayer, or is it one of Satan's gradual traps, as in the words of Ibn ul-Qayyim (may Allah have mercy on him),

Satan calls for seventy doors to goodness, either to use it as a way of reaching a door to evil or to use it to pass up a good greater, more glorious and more excellent than these seventy doors.

In the name of Allah, the Most Merciful, the Grantor of Mercy

All praise belongs to Allah, and may prayers and peace be upon Allah’s final Messenger.

Attending the congregational prayer is one of the causes of khushoo`; leaving it is not. You are correct in saying that this is Satan's way of gradually misleading people. Suffice it to say what was said by Abdallah ibn Mas`ood (may Allah be pleased with him),

You have seen us and no one misses it [the prayer], except the known hypocrite. In fact, a man would be brought to it being carried between two men until he stands in the row.

And Allah the Exalted knows best.

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