Whatever one eats does not defile him (Mark 7:18-19). This passage reads, “And he [Jesus] said to them, ‘Do you not see that whatever goes into a man from outside cannot defile him, since it enters not his heart but his stomach and so passes on?’ (Thus he declared all foods clean.)”
This section actually relates to eating with unwashed “defiled” hands (Mark 7:1-5). Jesus then explained that the Pharisees were only concerned with what went into their mouths, but what really defiles a person are evil thoughts from the heart within.