Some people are thought to be wise because they don’t talk much; others are disliked because they talk too much. Some people keep quiet because they don’t have anything to say; others keep quiet because they know the right time to speak. A wise person will not speak until the right moment, but a bragging fool doesn’t know when that time is.

[ἔστιν σιωπῶν εὑρισκόμενος σοφός,
καὶ ἔστιν μισητὸς ἀπὸ πολλῆς λαλιᾶς.
ἔστιν σιωπῶν, οὐ γὰρ ἔχει ἀπόκρισιν,
καὶ ἔστιν σιωπῶν εἰδὼς καιρόν.
ἄνθρωπος σοφὸς σιγήσει ἕως καιροῦ,
ὁ δὲ λαπιστὴς καὶ ἄφρων ὑπερβήσεται καιρόν.]

The Bible (The Old Testament) (14th - 2nd C BC) Judeo-Christian sacred scripture [Tanakh, Hebrew Bible], incl. the Apocrypha (Deuterocanonicals)

Book 22b. Sirach (Ecclesiasticus) 20: 5ff (Sir 20:5–7) [tr. GNT (1992 ed.)]
    (Source)

More on the history and acceptance of this Apocryphal book here and here.

(Source (Greek)). Alternate translations:

There is one that keepeth silence, and is found wise: and another by much babbling becometh hateful.
Some man holdeth his tongue, because he hath not to answer: and some keepeth silence, knowing his time.
wise man will hold his tongue till he see opportunity: but a babbler and a fool will regard no time.
[tr. KJV (1611)]

There is one that holdeth his peace, that is found wise: and there is another that is hateful, that is bold in speech.
There is one that holdeth his peace, because he knoweth not what to say: and there is another that holdeth his peace, knowing the proper time.
A wise man will hold his peace till he see opportunity: but a babbler, and a fool, will regard no time.
[tr. DRA (1899)]

There is the man who keeps quiet and is considered wise,
another incurs hatred for talking too much.
There is the man who keeps quiet, not knowing how to answer,
another keeps quiet, because he knows when to speak.
A wise man will keep quiet till the right moment,
but a garrulous fool will always misjudge it.
[tr. JB (1966); NJB (1985)]

There are people who are silent
and are found to be wise,
and there are those who are hated
because they talk a lot.
There are those who keep silent
because they have nothing to say
in response,
and there are those who keep silent
because they know the right time.
Wise people keep silent
until the proper moment,
but those who swagger and are senseless will miss the right moment.
[tr. CEB (2011)]

Some people keep silent and are found to be wise,
while others are detested for being talkative.
Some people keep silent because they have nothing to say,
while others keep silent because they know when to speak.
The wise remain silent until the right moment,
but the arrogant and the fool miss the right moment.
[tr. NRSV (2021 ed.)]