Every Christian must worry about living a life in holiness, away from the sin and corruption of this world because the Bible cammands us that again and again. The Bible tells us that we should be imitators of God, and God is very holy, so we must strive to be imitators of Him and live a life that leads each day towards holiness.
The apostle Peter wrote:
16 for it is written: “Be holy, because I am holy.”
17 Since you call on a Father who judges each person’s work impartially, live out your time as foreigners here in reverent fear.
18 For you know that it was not with perishable things such as silver or gold that you were redeemed from the empty way of life handed down to you from your ancestors,
19 but with the precious blood of Christ, a lamb without blemish or defect.
1 Peter 1:16-19