'Religion' in the Bible

who knew me before from the outset of my life, if they would bear witness, that according to the strictest sect of our religion I lived a Pharisee.

If any one think himself to be religious, not bridling his tongue, but deceiving his heart, this man's religion is vain.

Pure and undefiled religion before God and the Father is this: to visit orphans and widows in their affliction, to keep oneself unspotted from the world.