Saint Paul: "You received a Spirit of adoption."

Brothers and sisters:

For those who are led by the Spirit of God are sons of God.
For you did not receive a spirit of slavery to fall back into fear,
but you received a Spirit of adoption,
through whom we cry, "Abba, Father!"
The Spirit himself bears witness with our spirit
that we are children of God,
and if children, then heirs,
heirs of God and joint heirs with Christ,
if only we suffer with him
so that we may also be glorified with him.

-- Rom 8:14-17

Filial adoption, in making us partakers by grace in the divine nature, can bestow true merit on us as a result of God's gratuitous justice. This is our right by grace, the full right of love, making us "co-heirs" with Christ and worthy of obtaining "the promised inheritance of eternal life." The merits of our good works are gifts of the divine goodness. "Grace has gone before us; now we are given what is due. . . . Our merits are God's gifts."

-- CCC 2009

(Photo by author: Steubenville students greet the Holy Father at a Wednesday general audience at Rome in the filial Holy Spirit of adoption, crying out "Papa" as they recognize in Him our vicar of Christ on earth and a sign and source of unity for the Church in the heavenly Father's divine love.)