The Catechism in Questions & Answers

327. How is the promise of a “long life” to be understood today?

When children honour their parents out of love and gratitude, and thus appreciate them, obey them, and take care of them, the blessing of God will rest upon them. This blessing will reveal itself primarily in spiritual gifts.
In the understanding of the people of the Old Testament, “long life” was an expression of God’s blessing. In the new covenant, the blessing of God is demonstrated primarily in spiritual gifts.

Spiritual blessing: see Question 268.

Spiritual gifts come from God and make the believer “rich”. Among others, these spiritual gifts include love, patience, joy out of the Holy Spirit, knowledge of the truth of the gospel, childhood in God, forgiveness of sins, the sacraments, hope in the fulfilment of God’s promises, and sharing in these promises.