'Uncontaminated' in the Bible

Clean out the old leaven so that you may be a new batch, just as you are, still unleavened. For Christ our Passover Lamb has been sacrificed.

so that you may prove yourselves to be blameless and guileless, innocent and uncontaminated, children of God without blemish in the midst of a [morally] crooked and [spiritually] perverted generation, among whom you are seen as bright lights [beacons shining out clearly] in the world [of darkness],

Pure and unblemished religion [as it is expressed in outward acts] in the sight of our God and Father is this: to visit and look after the fatherless and the widows in their distress, and to keep oneself uncontaminated by the [secular] world.