Rom 14:15-19

Rom 14:15 But if your brother is grieved with your food, you no longer walk according to love. Do not with your food destroy him for whom Christ died.
Rom 14:16 Then do not let your good be spoken evil of,
Rom 14:17 for the kingdom of God is not eating and drinking, but righteousness and peace and joy in the Holy Spirit
Rom 14:18 For he who serves Christ in these things is well-pleasing to God, and approved by men.
Rom 14:19 So then let us pursue the things of peace, and the things for building up one another.

Here Paul is talking about food as example. How about subsititue the food with other things like clothes, words, books, etc. I believe it do apply to what we wear, how we talk, what we read, how we play. Basically, it is how we behave and how we present ourselves as sons and daughters of God who is above all else.

Think about it, we are prince and princess of the most high God, why we want to behave as a slave to the world?