During the period when Imam Baqir (as) was in the captivity of Mansur Dawaniqi (the second ‘Abbasid Caliph), he used to eat very little food. Once, a righteous lady who was the follower of the Ahlul Bayt prepared two loaves of bread by lawful means and sent it to the Imam (as) so that he could eat them. The jail warden said to Imam (as): “A certain pious lady, who happens to be your follower has sent these loaves as a present for you and has sworn that it has been made out of lawful means and has requested you to eat them.”
The Imam (as) refused to accept the loaves and asked for them to be returned to the lady.
“Tell her: We know that your food is lawful; however, since you have made it reach us by unlawful means, it does not befit us to eat it,” he said.( Lataif al-Tawaif, Page 44)