Your saying I should ask God to remove the impurities from my life?
I guess 'remove' wasn't the right word to use. Disarm is probably a better word.
In terms of food (since I brought it up, lol), though impurity/contamination may be there, you ask God, though grace, to overcome the power it has to potentially make you ill.
As far as sin, I'm saying Jesus' finished work on the cross (grace) has cover
ed your sins and you would be asking to, likewise, break the sinful yolks in your life. Which is basically asking for a closer, more faithful relationship with God, because most habitual sin is a lack of trust in God's provision.
(the passage that the verse in my signature is from, talks about trusting in God and his provision)