الكافي- ط الاسلامية, volume 3, page 297

3. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ‘Uthman ibn ‘Isa from ibn Muskan from ibn abu Ya‘fur who has said the following: “I once asked abu ‘Abd Allah (a.s.), about a man whose Salah (prayer) is discontinued because of something moving in front of him. He (the Imam) said, ‘Things do not discontinue Salah (prayer) of the believer, but guard it as much as you can.’” “In the narration of ibn Muskan from abu Basir from abu ‘Abd Allah (a.s.), it is said that things do not discontinue Salah (prayer), not a dog, donkey and woman, but place a barrier in front of yourselves, of the size of one yard high above ground; it is enough of a barrier.’” Al-Kulayni has said that it is better to establish a barrier with something, which you can place in front of yourselves and those passing-by. If you did not do so, it is not harmful because the one for whom one performs Salah (prayer) is closer than passing-by one, but it is a matter of the discipline of Salah (prayer) and its respect.

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

4. Ali ibn Ibrahim has narrated from his father in a marfu’ manner from Muhammad ibn Muslim who has said the following: “Once, abu Hanifah went to see abu ‘Abd Allah (a.s.). On his arrival he said, ‘I saw your son Musa perform Salah (prayer) while people passed by in front of him; but he did not stop them and it is questionable.’ Abu ‘Abd Allah (a.s.), asked to call Musa. He was called and he asked, ‘Son, abu Hanifah says that you were performing Salah (prayer) and people passed by in front of you, but you did not stop them.’ He replied, ‘Yes, O father, the One for whom I was performing Salah (prayer) was closer to me than people passing by in front of me. Allah, most Majestic, most Glorious, says, “We are closer to him than the jugular vein.’” (50:16) The narrator has said that he (the Imam) then embraced him and then said, ‘I pray to Allah to keep me and my mother in service for your cause, O reservoir of secrets.’ (Imam’s response is to show the significance of Salah (prayer) not to compromising any excellence.)”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.