And there are plenty of verses showing that what we eat isn't a requirement and that everything is clean. You don't have to use mark 7:19.
Romans 14:1-23
As for the one who is weak in faith, welcome him, but not to quarrel over opinions. One person believes he may eat anything, while the weak person eats only vegetables. Let not the one who eats despise the one who abstains, and let not the one who abstains pass judgment on the one who eats, for God has welcomed him. Who are you to pass judgment on the servant of another? It is before his own master that he stands or falls. And he will be upheld, for the Lord is able to make him stand. One person esteems one day as better than another, while another esteems all days alike. Each one should be fully convinced in his own mind.
Be convinced in your own mind in what you do. There is no need to be convincing anyone else.
Romans 14:14
I know and am persuaded in the Lord Jesus that nothing is unclean in itself, but it is unclean for anyone who thinks it unclean.
Again this is personal on how you feel about something. It could be applied to Pork or anything for that matter.
Acts 15:29
That you abstain from what has been sacrificed to idols, and from blood, and from what has been strangled, and from sexual immorality. If you keep yourselves from these, you will do well. Farewell.”
No mention of pork and there easily could have been if it was important. Meat sacrificed to idols is mentioned here as something to abstain from yet it is also mentioned as being fine for others to eat in 1 Cor.
4 Therefore, as to the eating of food offered to idols, we know that “an idol has no real existence,” and that “there is no God but one.”
7 However, not all possess this knowledge. But some, through former association with idols, eat food as really offered to an idol, and their conscience, being weak, is defiled.
What was important was that by eating a person could make another brother stumble, that was the real issue. Not whether the roast happened to be pork or beef, sacrificed to an idol or not.
Romans 14:20
Do not, for the sake of food, destroy the work of God. Everything is indeed clean, but it is wrong for anyone to make another stumble by what he eats.
Matthew 15:11
It is not what goes into the mouth that defiles a person, but what comes out of the mouth; this defiles a person.