some Latin sentences

[Zefiro]

My best wishes to all of you.

These 2 bits of Latin were found on an old sheet of parchment filled with biblical verses. I suspect they were 'left-overs' from an earlier use of this parchment, so probably an incomplete palimpsest.
Is anyone able to read them and tell what there all about?
I have little experience with this kind of writing.

I'll be very grateful.

[Zefiro]

second one

[Bookbox]

The second extract seems to read …

... medicinalibus sunt instituta
ieiunijs P(er) ...

An online search suggests this is a liturgical text from a Catholic missal. It offers an early Norwegian source, Missale Nidrosiense, 1519 (though perhaps the text itself occurs in other missals as well?)

https://www.bokselskap.no/boker/missale/part1
(scroll down to Feria Quinta - Secreta)

I haven't tackled your first excerpt yet, but maybe it's from a similar source?

[Bookbox]

The first extract - or something very similar - does appear in the same source, under Feria Tertia, just above the next heading Feria Quarta ...

[Complenda S]anctificationibus tuis, omnipotens deus, et vitia nostra curentur et remedia nobis sempiterna proueniant. Per dominum.

[Zefiro]

Bookbox,
thank you for your answer. Very helpful, as always. I have to admit that I was surprised that both pieces were liturgical as well. I really thought they didn't belong on the page.
The rest of the page was a collection of biblical texts mixed with psalms. Together with this pieces, I think the whole forms a kind of blueprint for a Holy Mass.

[Bookbox]

Certainly looks like it. If you ever need help with difficult liturgical MSS, there are some very good people in this Facebook group ...
https://www.facebook.com/groups/1557478997849423