St. Thomas Aquinas differentiates between the active and contemplative lives based on their respective goals and activities. The active life focuses on external actions, such as serving others and working for the present world's needs, while the contemplative life centers on seeking truth and God through contemplation and prayer.
The active life is meritorious due to its focus on loving God and neighbor, but the contemplative life is considered superior because it directly pertains to the love of God, which is the ultimate end of human life. The contemplative life is more meritorious because it involves a deeper union with God, leading to a higher form of happiness and fulfillment. However, the active life is also valuable, as it prepares individuals for the contemplative life and allows them to contribute to the world's well-being. Both lives are essential in the Mystical Body of Christ, the Church.