An Explanation of Luther's Small Catechism · Martin Luther
II. HIS WORK.
The work of the Holy Ghost is _Sanctification_. This word is used here, at the head of the Third Article, in the wide sense, and includes the Holy Spirit's entire work upon our souls; namely, Calling, Enlightening, Sanctification in the narrower sense, and Preservation in the Faith. 1. ITS NECESSITY. If the Holy Spirit does not work in us, we cannot be saved. Hence, we say in the catechism, I BELIEVE THAT I CANNOT BY MY OWN REASON OR STRENGTH BELIEVE IN JESUS CHRIST MY LORD, OR COME TO HIM. For as I am by nature, my _reason_ is so darkened by sin, [I Cor. 2:14+] that I do not see my need of the Saviour; and I am so lacking in spiritual _strength_ (being dead in trespasses and sins), [Eph. 2:1] that I am unable to believe in Christ. Consequently it is necessary that the Holy Spirit should teach me to see in Christ my only Saviour, and give me strength to believe in Him.
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