“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.” (Romans 14:1-4 ESV)

Apparently, in the Roman church, there were some confident in their freedom in Christ who ate all foods.  And there were others who still maintained a dietary regimen.  Paul is merely encouraging them not to despise each other.  We get so passionate about issues that it can divide the church.  While I may disagree with you on an issue, I can see that you are passionately pursuing obedience to Christ.  Each group was doing their best to obey God in the way they understood.  And yet, they weren’t happy with that; they wanted the other group to change.  We see this so much in the modern church.  Where it’s an issue of worship styles, or Armenian vs. Calvinist, or anything else, we would rather hate and disagree than love and appreciate that we all are trying to know and love God the best we can.  God did not make the members of the church the same; He asked us to live in unity.  There is no need for unity when all is conformity.  There is need for unity when we are different.  That is one of the things that makes the church of Jesus beautiful.  It is artwork with many differing pieces with different looks, shapes, and purposes, but together make a lovely whole.