I believe that it matters what we choose to watch, read, listen to and do because all of these things make their way into our heart and whether we know it or not, it helps to form who we are. That is why the bible encourages us to think on heavenly things. If we fill our minds with sinful things, slowly our brains get washed into believing that these sinful things “aren’t that bad”. We get desensitized to the truth that sin is sin, and that all sin separates us from God. But if we concentrate on heavenly things positive washing can occur. Our brains and hearts can be washed with the things of God making us more and more into his likeness and stirring our faith and love towards him. The bible teaches us that we gain faith by reading God’s word. The more we are connected with the things of God, the more our hearts and minds begin to conform to him. That is why it says in Luke chapter 11, verses 34 through 36:
"Your eye is the lamp of your body. When your eyes are good, your whole body also is full of light. But when they are bad, your body also is full of darkness. See to it, then, that the light within you is not darkness. Therefore, if your whole body is full of light, and no part of it dark, it will be completely lighted, as when the light of a lamp shines on you."
Every believer would agree that they would like their body to be full of light. To do that, we need to be mindful of what we allow into our hearts by way of what we see, hear and do.
I encourage you to make every effort to ensure that your body is full of light. Read the bible, pray to God, spend time with other believers, listen to Christian music and podcasts, figure out ways to think on heavenly things and put Godly thoughts into your heart and mind. That really is the only way that we can make sure that the light within us is not darkness - as Jesus says.