Iudex dicit testimonium servae tam grave esse quam testimonium militis.

Because Latin often uses an indirect statement after verbs of saying, thinking, knowing, and similar verbs.

Here, dicit means says, and what follows is the content of what the judge says:

• testimonium servae ... esse ...
• literally: the testimony of the slave woman to be ...

In natural English we would usually say:

• The judge says that the slave woman’s testimony is as weighty as the soldier’s testimony.

But Latin normally prefers:

• says + accusative subject + infinitive
• this construction is often called the accusative-and-infinitive.

So esse is there because Latin expresses is inside indirect statement as to be.

It actually is accusative here, but the form looks the same as the nominative.

Testimonium is a neuter second-declension noun. For neuter nouns, the nominative singular and accusative singular are identical.

So:

• nominative singular: testimonium
• accusative singular: testimonium

In this sentence, the first testimonium is the subject of the infinitive esse, so in an indirect statement it goes into the accusative.

Servae is genitive singular here, meaning of the slave woman or the slave woman’s.

So:

• testimonium servae = the testimony of the slave woman

A native English speaker may notice that servae could also be dative singular or nominative plural in other contexts. That is true. But here the meaning and structure make genitive singular the correct choice.

So this is not:

• for the slave woman
• or slave women

It is:

• of the slave woman

Militis is also genitive singular, meaning of the soldier or the soldier’s.

So:

• testimonium militis = the testimony of the soldier

It looks different from servae because the two nouns belong to different declensions:

• serva, servae = first declension
• miles, militis = third declension

They are doing the same grammatical job, but their genitive singular endings are different because their dictionary forms belong to different noun patterns.

This is the standard Latin pattern for as ... as ... comparisons.

• tam = so / as
• quam = than / as

Together, in this type of sentence, they mean:

• as weighty as
• as serious as

So:

• tam grave esse quam testimonium militis
• = to be as weighty as the testimony of the soldier

This is the normal way Latin expresses equality in a comparison.

Because grave agrees with testimonium.

Testimonium is:

• singular
• neuter

So the adjective describing it must also be:

• singular
• neuter

That gives us grave.

The adjective is not agreeing with servae or militis. It is describing the testimony, not the people.

So the sense is:

• the testimony is weighty not
• the slave woman is weighty or
• the soldier is weighty

Yes, gravis, grave originally has the idea of heavy, but it often has a broader meaning such as:

• serious
• important
• weighty
• influential

In this sentence, grave is probably best understood as something like:

• weighty
• serious
• important

So the judge is saying that the slave woman’s testimony carries as much importance or force as the soldier’s testimony.

Yes, Latin could sometimes leave it out if the meaning were clear, just as English can say:

• the slave woman’s testimony is as weighty as the soldier’s

without repeating testimony.

But repeating testimonium here makes the comparison very clear and balanced:

• testimonium servae
• testimonium militis

It is neat, formal, and easy to understand. Latin often likes this kind of parallel structure.

It is feminine.

The base noun is:

• serva = female slave / slave woman

That is different from:

• servus = male slave

So testimonium servae specifically means:

• the testimony of the female slave
• not just the testimony of a slave in a gender-neutral sense

Yes, it matters, because Latin marks grammatical gender clearly in the noun itself.

A helpful way to unpack it is:

• Iudex dicit
• testimonium servae
• tam grave esse quam testimonium militis

More literally:

• The judge says
• the testimony of the slave woman
• to be as weighty as the testimony of the soldier

In smoother English:

• The judge says that the slave woman’s testimony is as weighty as the soldier’s testimony.

Latin word order is more flexible than English word order, but this sentence is still quite orderly:

• main verb first: dicit
• then the indirect statement
• then the comparison

Not very naturally.

A very literal version would be:

• The judge says the testimony of the slave woman to be as weighty as the testimony of the soldier.

That is understandable, but it sounds unnatural in normal English.

A better English translation is:

• The judge says that the slave woman’s testimony is as weighty as the soldier’s testimony.

This is a good example of how Latin and English often use different grammar to express the same idea:

• Latin: accusative + infinitive
• English: that-clause