“The Creed is divided into three main parts, each telling about one of the three persons of the holy and divine Trinity. The first–the Father; the second–the Son; and the third–the Holy Spirit. The latter is the most important article of the Creed; all the others are based on it.” (page 24)

Luther, Martin. “Personal Prayer Book” (1522) Luther’s Works Vol. 43. (Philadelphia: Fortress Press, 1968), page 24.

{I was surprised that he doesn’t say here that the 2nd article on Jesus is the most important; this must be because it is the Holy Spirit who has called us by the Gospel, enlightened us with His gifts, sanctified and kept us in the true faith [his Small Catechism on the 3rd article of the Creed] — that’s what makes the objective justification won on the cross and in the empty tomb meaningful to each and every one of us, that is, subjective}