Some solid reminders from the Hebrews reading, and a bit of a stutter in the gospel reading. If anyone is using the alternate first reading, Sirach does get cited in the Book of Concord, but not chapter 10. Also, good on ya' for using Sirach.
Hebrews 13:1-8, 15-16
Verse 15 is cited twice. First as a quote in Apology of the Augsburg Confession, Article 24: The Mass (AP 24.26) to drive home the point that our spiritual worship is not some kind of sacrifice that works on its own--that simply by doing it we have earned God's favor. Rather the attitudes we have when we offer our worship to God matter, and it is only by the Holy Spirit, giving the gift of faith in Jesus, that we are able to offer our spiritual worship.
Verse 15 is cited in an editorial insert in Formula of Concord, Solid Declaration, Article 6: Third Use of the Law (SD 6.22) providing a fuller citation for those originally provided. The argument at this point is direct. The law demands that humans, to be acceptable to God, always follow the law. Any breach of the law makes a person and their worship unacceptable. The gospel, however, shows that through faith in Jesus, our worship is acceptable.
Luke 14:1, 7-14
There is a citation here, but it's the section that's cut out. Verses 1-6 are cited in a footnote to The Large Catechism, The First Part: The Ten Commandments, The Third Commandment (LC 1.81), which we ran into last week. The skipped scene is very reminiscent of the Lectionary 21 C gospel reading, which is probably why it was skipped. However, it does present an interesting case of the lawyers and Pharisees having learned from the incident with the leader at the synagogue. In any case, the list of these citations is present for the same reason as last week: giving examples of people who "slandered Christ and would not permit him to do the very same things they themselves did on that day" (LC 1.81) to make the point that the commandment to rest cannot be kept simply by not doing work.
A simple, but always necessary reminder: the faith that the Spirit gives is us what makes the work of the people acceptable to God. And because I'm guessing that none of us spend enough time in Sirach, here's that alternative reading:
The beginning of human pride is to forsake the Lord;
the heart has withdrawn from its Maker.
For the beginning of pride is sin,
and the one who clings to it pours out abominations.
Therefore the Lord brings upon them unheard-of calamities,
and destroys them completely.
The Lord overthrows the thrones of rulers,
and enthrones the lowly in their place.
The Lord plucks up the roots of the nations,
and plants the humble in their place.
The Lord lays waste the lands of the nations,
and destroys them to the foundations of the earth.
He removes some of them and destroys them,
and erases the memory of them from the earth.
Pride was not created for human beings,
or violent anger for those born of women.
-- Sirach 10:12-18 (NRSV)
That should be more than enough for reflection this week.