Is there a point to be made here about lack of the definite article?
A point? And how does this have any relevance to the resurrection/glorification of believers?
OK, according to biblestudytools.com these are the subheading of the chapter:
Appointed festivals
Sabbath
Passover and festival of unleavened bread
Offering the firstfruits
Festival of weeks
Festival of trumpets
Day of Atonement
Festival of Tabernacles
So these are all the verses under "firstfruits"
Offering the Firstfruits
9 The LORD said to Moses,
10 “Speak to the Israelites and say to them: ‘When you enter the land I am going to give you and you reap its harvest, bring to the priest a sheaf of the first grain you harvest.
11 He is to wave the sheaf before the LORD so it will be accepted on your behalf; the priest is to wave it on the day after the Sabbath.
12 On the day you wave the sheaf, you must sacrifice as a burnt offering to the LORD a lamb a year old without defect,
13 together with its grain offering of two-tenths of an ephah of the finest flour mixed with olive oil—a food offering presented to the LORD, a pleasing aroma—and its drink offering of a quarter of a hin of wine.
14You must not eat any bread, or roasted or new grain, until the very day you bring this offering to your God. This is to be a lasting ordinance for the generations to come, wherever you live.
I see nothing here that is relevant to 1 Cor 15:23. So, what is your point by bringing Lev 23 up?
And?? The point, please.
Well, you're going to have to actually connect the dots.
Since none of the verses cited in your post are relevant to 1 Cor 15:23 and Christ being the "firstfruits" in regard to glorification, yo've not made any coherent point.