The text is a meditation on the suffering and death of Christ, which brought eternal life to believers (st. 1), provided full atonement for our sin (st. 2), and mortified our "old nature" (st. 3). The tone of unending gratitude to God reflected in the refrain line–"thousand, thousand thanks are due"–runs throughout the entire text.
This song is saturated with an awareness of the vicarious suffering of Christ, for this we owe him a “…thousand, thousand thanks.” Belgic Confession, Article 21 captures the heart of our confidence and assurance with its profession: “And he endured all this for the forgiveness of our sins.”