“I once was with abu Ja‘far, when abu ‘Abd Allah (a.s.), came. Abu Ja‘far, said, ‘You must cleanse your shirt.’ He left and we thought his shirt might have come in contact with something unclean. He came back and he (the Imam) said, ‘It just is as it was.’ We then asked saying, ‘We pray to Allah to keep our souls in service for your cause, what is wrong with his shirt?’ He (the Imam) said, ‘His shirt is long and I commanded him to shorten it; because Allah, most Majestic, most Glorious, has said, ‘. . . and cleanse (shorten) your clothes.’ (74:4)”