Postquam vinum in aram fuderit, sacerdos puellis pacem optabit.

Postquam is a conjunction meaning after. It introduces the subordinate clause postquam vinum in aram fuderit and shows that this action happens before the action in the main clause sacerdos puellis pacem optabit.

So the structure is:

• postquam ... fuderit = after ... has poured
• sacerdos ... optabit = the priest will wish ...

Latin often uses a subordinate clause like this to mark the earlier action clearly.

Here fuderit is best understood as future perfect indicative, not subjunctive.

That is a very common Latin pattern:

• postquam
  • future perfect
• main clause in the future

So the sense is:

• After he has poured the wine onto the altar, the priest will wish peace to the girls.

Latin uses the future perfect to show that one future action will be completed before another future action happens.

Also, fuderit comes from fundo, fundere, fudi, fusum (pour). The perfect stem is fud-, so:

• fuderit = he/she will have poured

Formally, fuderit could also look like a perfect subjunctive, but the context here strongly points to the future perfect indicative.

Latin verbs usually include the subject inside the verb ending.

So fuderit already means:

• he will have poured
• she will have poured
• or even it will have poured, depending on context

Latin often leaves the subject unstated unless it needs emphasis or clarification.

In this sentence, the most natural understood subject is the same person later identified as sacerdos.

Vinum is the direct object of fuderit.

The verb fundere means to pour, and the thing being poured is the direct object. In Latin, direct objects are usually in the accusative case.

So:

• vinum = the wine as the thing poured

Because in can take two different cases depending on its meaning:

• in + accusative = into / onto, showing motion toward
• in + ablative = in / on, showing location

Here the wine is being poured onto the altar, so Latin uses in aram with the accusative.

Compare:

• in aram = onto the altar
• in ara = on the altar or in the altar as a location

Sacerdos is nominative singular, and it is the subject of optabit.

Even though the ending -os may look unusual to an English-speaking learner, sacerdos is a third-declension noun. Its nominative singular form is simply sacerdos.

It is the subject because:

• it is in the nominative case
• optabit is a singular verb
• the meaning fits: the priest will wish peace...

Not necessarily. Sacerdos is a noun that can refer to either a priest or a priestess, depending on context.

Latin often uses the same noun form for both sexes with words like this. If the wider context does not specify gender, the word itself does not force us to choose.

Puellis is dative plural.

It is used as the indirect object with optabit. The idea is:

• pacem = the thing wished
• puellis = the people to or for whom it is wished

So:

• puellis pacem optabit = he will wish peace to/for the girls

The dative often marks the person affected by an action in this way.

Pacem is the direct object of optabit.

The verb optare means to wish or to desire, and the thing being wished is put in the accusative.

So in this sentence:

• pacem = peace, the thing wished
• puellis = to/for the girls, the indirect object

That is why the sentence has both:

• an accusative direct object
• a dative indirect object

The ending -bit marks the future tense for many third-conjugation and fourth-conjugation verbs.

So:

• optat = he/she wishes
• optabit = he/she will wish

This future main verb fits well with fuderit as future perfect:

• after he has poured ...
• the priest will wish ...

Latin word order is much more flexible than English word order because the cases and verb endings show the grammatical relationships.

This sentence could be rearranged in several ways without changing the basic meaning, for example:

• Sacerdos postquam vinum in aram fuderit, puellis pacem optabit.
• Pacem sacerdos puellis optabit postquam vinum in aram fuderit.

The original order is natural and clear:

1. the earlier action first
2. then the main action

Latin often places words for emphasis or style rather than because of a fixed word-order rule.

The sentence describes two future actions, but one happens before the other.

1. postquam vinum in aram fuderit
   = first, the pouring will be completed

2. sacerdos puellis pacem optabit
   = then, the priest will wish peace to the girls

That is exactly why Latin uses:

• future perfect for the earlier future action
• future for the later future action

English often does something similar with after he has poured ... he will wish ...