(3) And because ye are sons, God hath (f) sent forth the (g) Spirit of his Son into your hearts, crying, Abba, Father.
(3) He shows that we are free and set at liberty in such a way that in the meantime we must be governed by the Spirit of Christ, who while reigning in our hearts, may teach us the true service of the Father. But this is not to serve, but rather to enjoy true liberty, as it is fitting for sons and heirs.
(f) By that which follows he gathers that which went before: for if we have his Spirit, we are his sons, and if we are his sons, then we are free.
(g) The Holy Spirit, who is both of the Father, and of the Son. But there is a special reason why he is called the Spirit of the Son, that is, because the Holy Spirit seals up our adoption in Christ, and gives us a full assurance of it.