When a sieve is shaken, the refuse appears;
so does a person’s waste when he speaks.
The kiln tests the potter’s vessels,
and the test of a person is in his conversation.
Its fruit discloses the cultivation of a tree;
so does speech the thoughts of the human mind.
Do not praise anyone before he speaks,
for this is the way people are tested.

[Ἐν σείσματι κοσκίνου διαμένει κοπρία,
οὕτως σκύβαλα ἀνθρώπου ἐν λογισμῷ αὐτοῦ.
σκεύη κεραμέως δοκιμάζει κάμινος,
καὶ πειρασμὸς ἀνθρώπου ἐν διαλογισμῷ αὐτοῦ.
γεώργιον ξύλου ἐκφαίνει ὁ καρπὸς αὐτοῦ,
οὕτως λόγος ἐνθυμήματος καρδίας ἀνθρώπου.
πρὸ λογισμοῦ μὴ ἐπαινέσῃς ἄνδρα·
οὗτος γὰρ πειρασμὸς ἀνθρώπων]

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

Book 22b. Sirach (Ecclesiasticus) 27: 4ff (Sir 27:4–7) [tr. NRSV (2021 ed.)]
    (Source)

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

(Source (Greek)). Alternate translations:

As when one sifteth with a sieve, the refuse remaineth; so the filth of man in his talk.
The furnace proveth the potter's vessels; so the trial of man is in his reasoning.
The fruit declareth if the tree have been dressed; so is the utterance of a conceit in the heart of man.
Praise no man before thou hearest him speak; for this is the trial of men.
[tr. KJV (1611)]

As when one sifteth with a sieve, the dust will remain:
so will the perplexity of a man in his thoughts.
The furnace trieth the potter's vessels,
and the trial of affliction just men.
Be the dressing of a tree sheweth the fruit thereof,
so a word out of the thought of the heart of man.
Praise not a man before he speaketh,
for this is the trial of men.
[tr. DRA (1899), 27:5–8]

In a shaken sieve the rubbish is left behind,
so too the defects of a man appear in his talk.
The kiln tests the work of the potter,
the test of a man is in his conversation.
The orchard where the tree grows is judged on the quality of its fruit,
similarly a man's words betray what he feels.
Do not praise a man before he has spoken,
since this is the test of men.
[tr. JB (1966)]

In a shaken sieve the rubbish is left behind,
so too the defects of a person appear in speech.
The kiln tests the work of the potter,
the test of a person is in conversation.
The orchard where the tree grows is judged by its fruit,
similarly words betray what a person feels.
Do not praise anyone who has not yet spoken,
since this is where people are tested.
[tr. NJB (1985)]

Your talk shows your faults; it is like a sieve that separates out the rubbish. The way you think shows your character just as surely as a kiln shows any flaws in the pottery being fired. You can tell how well a tree has been cared for by the fruit it bears, and you can tell a person's feelings by the way he expresses himself. Never praise anyone before you hear him talk; that is the real test.
[tr. GNT (1992 ed.)]

When a sieve is shaken,
rubbish remains behind;
so in the process of reasoning,
a person’s flaws appear.
A kiln tests a potter’s jars,
and decision making tests a person.
A tree’s fruit reveals
how well it has been cultivated.
In the same way, reasoning makes plain
a person’s thoughts.
Don’t praise people
until after they present an argument,
for this is how people are tested.
[tr. CEB (2011)]