Do not pass in front of someone praying

Waiting forty would be better than walking in front of a person praying.

Narrated by Abu Juhaim

If the one who passes in front of a person praying knew what is upon him, it would be better for him to stand for forty than to pass in front of him.

Sahih al-Bukhari 510, Sahih Muslim 507

What this hadith teaches

The narrator was not sure whether forty days, months or years were meant. Wait, or go around behind, or pass beyond the sutrah.

Reference and grade

Grade
Sahih: agreed upon by al-Bukhari and Muslim
Narrator
Abu Juhaim

The hadith in Arabic نص الحديث

لَوْ يَعْلَمُ الْمَارُّ بَيْنَ يَدَىِ الْمُصَلِّي مَاذَا عَلَيْهِ لَكَانَ أَنْ يَقِفَ أَرْبَعِينَ خَيْرًا لَهُ مِنْ أَنْ يَمُرَّ بَيْنَ يَدَيْهِ

Arabic text of Sahih al-Bukhari 510, as given on sunnah.com.