The Purchase of the Pure

This morning I was meditating on the first 5 verses of Revelation 14. These verses speak of 144,000 who are spiritually undefiled. They are like pure virgins. They are also described as redeemed from the earth and purchased from among the people of the earth.
The sense I get is that this is not a purity that is achieved. Instead, it is something given to us as unmerited favor.
There is hope for us in this. Even though we may at times feel defiled by the world, God is still making us pure. He is redeeming us from a place that is so contrary to Him and making us blameless.