When we talk about redemption, that is Biblical or Christian Redemption, we are talking about the deliverance of true believers from sin.
Most everyone, even non-believers have heard John 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. Christ came to be the redeemer of lost sinners souls, to all those who would answer the Fathers call.
Charles Haddon Spurgeon February 28, 1858
Scripture: Matthew 20:28 From: New Park Street Pulpit Volume 4
Redemption and its Claims by C H Spurgeon
The Significance of Genesis 3:15 by Derek Thomas