Reverts often find difficulty in how to approach and deal with their non-Muslim parents after their conversion. Especially when it comes to eating their food and purity issues. Imam al-Sadiq (as) gives some amazing advice:

Zakariya ibn Ibrahim said: “I was a Christian, then I became a Muslim. I went for Hajj, where I met abu ‘Abd Allah (as) and I said to him, ‘I was a Christian and I have become a Muslim.’ The Imam asked, ‘What have you seen in Islam?’ I said, ‘They are the words of Allah, the Most Majestic, the Most Holy, “. . . before, you did not even know what a Book or belief was, but We have made the Quran as a light by which We guide whichever of Our servants We want.”’ (42:52)
The Imam said, ‘Allah has certainly granted you guidance.’ The Imam then said three times: ‘O Allah, guide him. Son, ask whatever you want to ask.’ I then said, ‘My parents and my family are Christians and my mother is blind. I live with them. Can I eat from their utensils with them?’ The Imam asked, ‘Do they eat pork?’ I said, ‘No, they do not even touch it.’ The Imam said, ‘There is no offense in your eating with them. Take good care of your mother and be kind to her. When she will die do not leave her to others. You must do everything that she will need (for her funeral). Do not tell anyone of your meeting with me until you will meet me at Mina, if Allah would so will.’
I (the narrator) met him at Mina and people were around him as if he were the teacher of children. He asks a question then the other asks a question and so on.
I returned to Kufa and I would act more kindly toward my mother. I would feed my mother, wash her clothes, her head and would serve her in other ways.’ She said, ‘My son, you did not do all this for me when you followed my religion. What is all that I see from you after you left and accepted the religion of submission (Islam)?’ I said, ‘A man from the descendants of our prophet has commanded me to do all this.’ She then asked, ‘Is this man a prophet?’ I said, ‘No, but he is a descendant of a prophet.’ She said, ‘My son, he is a prophet; these are of the teachings of the prophets.’ I said, ‘Mother, there will be no other prophet after our prophet. He is a descendant of our prophet.’ She then said, ‘Your religion is the best religion. Explain it to me.’ I then explained to her and she accepted Islam. I taught her more. She prayed, Zuhr, ‘Asr, Maghrib and ‘Isha’ prayers.
Thereafter something happened to her at night and she said, ‘Son, explain and repeat to me what you told me about Islam and I repeated it to her. She affirmed them and then she died. In the morning the Muslims were the ones who helped with her funeral and washed her. I was the one who prayed on her body and climbed down in her grave (to place her body to rest).’”

Sanad: A number of our people have narrated from Ahmad ibn Muhammad ibn Khalid from Ali ibn al-Hakam from Mu’awiyah ibn Wahab from Zakariya ibn Ibrahim who has said the above hadith

Source: al-Kafi, Volume 2, Chapter 69, Hadith #11 (See Image below)