The life of prayer for the child of God is worked by the Holy Spirit. JohnCalvin argues that it is through Christ and his work that the believer can now enter boldly before God and pray because the veil has been torn away between sinners and God through Christ’s ministry of reconciliation.
It is however, the Spirit that works boldness in the hearts of believers to go to God in prayer through Christ, and Calvin highlights the necessity of enlisting the help of the Spirit in prayer. The Spirit assists the believer despite their weaknesses in prayer, “if we remember that God is still our Father and that we must seek refuge in him.” With the witness and testimony of the Spirit with the believer’s spirit comes true prayer. This is affirmed when Calvin argues from biblical evidence that unless the Spirit testifies in our hearts, working confidence regarding the Father’s love, “our tongues would be dumb, so that they could utter no prayers.” Right prayer issues forth from Spirit-worked assurance.
Calvin succeeds in demonstrating that this Spirit of prayer is not only present in the New Testament but also in the Old. The ministry of the Spirit of adoption is effectual for the Old Testament saints as well. He illustrates this effectively in the life and prayer of the prophet Habakkuk. The prophet prays in Habakkuk 3:1-2 for God to revive his work. This is nothing else than an appeal using the “favour of adoption.” He continues that the prophet “thus confesses that there was no reason why God should forgive his people except that he had been pleased freely to adopt them and to choose them as his peculiar people.”Calvin uses Habakkuk as a model for the prayer life of the adopted child of God when he says, “Now we have this in common with the ancient people, that God adopts us…We may therefore adopt this form of prayer, which is prescribed for us by the Holy Spirit.”
The Holy Spirit does not only aid in individual prayer for the people of God of certain ethnicity and language, but prayer can be offered by any person of any ethnicity or language. This is illustrated by the Spirit-indicted cry, “Abba, Father.” In using this phrase, Calvin uniquely argues that the adoption is both to the Jew and Gentile. The word Abba is Hebrew and the word Father is in Greek demonstrating that “we can call upon God in any language, as with one voice, confident that God will receive us now that we have the liberty to address him.” The Spirit’s witness in prayer is an integral part of the believer’s privilege of praying with boldness since as Griffith notes so well, “conviction of God’s holiness and our sin would preclude having the faith to call God ‘Father,’ apart from the witness of the Spirit of adoption in our hearts.”