Al-Mu'jam Al-Waseet [The Dictionary]
Volume One
Page 105

Translation

(Thumma [Then]): A letter of Atf [an Arabic grammatical classification] indicating sequence [in order] with a pause in time [between the two things in the sequence], like in the Most Exalted's [Allah's] saying: {He began the creation of man with (nothing more than) clay. And *Thumma* made his progeny from a quintessence of the nature of a fluid despised: But *Thumma* He fashioned him in due proportion and breathed into him something of His spirit} [Yusuf Ali, in reference to Quran verses 32:7-9].

Phrases between normal () parentheses are in the original text, while the ones between square [] brackets are mine.

As you see, Thumma (then) definitely means a sequence in order.

I just realized something, it's kind of funny actually how I'm trying to prove that Thumma must indicate sequence and order using a dictionary. It is just like trying to prove in English that "then" indicates sequence and order. You know, if you come up to an Arab and ask him if thumma may not indicate sequence or order he'll just laugh.

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