Here is how the Reformed Belgic Confession describes this work of the Spirit (“the Holy Ghost”), this hearing with faith, and that all things that we need for salvation are in Christ.
Article 22: Of Faith in Jesus Christ.
We believe that, to attain the true knowledge of this great mystery, the Holy Ghost kindleth in our hearts an upright faith, which embraces Jesus Christ, with all his merits, appropriates him, and seeks nothing more besides him. For it must needs follow, either that all things, which are requisite to our salvation, are not in Jesus Christ, or if all things are in him, that then those who possess Jesus Christ through faith, have complete salvation in him. Therefore, for any to assert, that Christ is not sufficient, but that something more is required besides him, would be too gross a blasphemy: for hence it would follow, that Christ was but half a Savior. Therefore we justly say with Paul, that we are justified by faith alone, or by faith without works. However, to speak more clearly, we do not mean, that faith itself justifies us, for it is only an instrument with which we embrace Christ our Righteousness. But Jesus Christ, imputing to us all his merits and so many holy works which he has done for us, and in our stead, is our Righteousness. And faith is an instrument that keeps us in communion with him in all his benefits, which, when become ours, are more than sufficient to acquit us of our sins.
Sola Christo (Christ Alone): “those who possess Jesus Christ through faith, have complete salvation in him.”. See above Article 22 of The Belgic Confession. Sola Christo (Christ Alone) is one of “The Five Solas” of the Reformation. (For further explanation of “The Five Solas“, see the tag on top of my web site.)
And, even faith is a gift of God.
“Faith is therefore to be considered as the gift of God, not on account of its being offered by God to man, to be accepted or rejected at his pleasure; but because it is in reality conferred, breathed, and infused into him; or even because God bestows the power or ability to believe, and then expects that man should by the exercise of his own free will, consent to the terms of that salvation, and actually believe in Christ; but because he who works in man both to will and to do, and indeed all things in all, produces both the will to believe, and the act of believing also.” Article 14 of the Reformed Canons of Dordt.