He wants for ever, who would more acquire;
Set certain limits to your wild desire.

[Semper avarus eget; certum voto pete finem.]

Horace (65-8 BC) Roman poet, satirist, soldier, politician [Quintus Horatius Flaccus]

Epistles [Epistularum, Letters], Book 1, ep. 2 “To Lollius,” l. 56ff (1.2.56) (20 BC) [tr. Francis (1747)]
    (Source)

(Source (Latin)). Other translations:

The Carle wantes aye, let thou thy drift to no excesse extende.
[tr. Drant (1567)]

The Cov'tous alwayes want: your pray'rs design
To some fixt mark.
[tr. Fanshawe; ed. Brome (1666)]

Desires are endless, till you fix the end.
[tr. "Dr. W."; ed. Brome (1666)]

The Greedy want, to Wishes fix an End.
[tr. Creech (1684)]

Draw some fix'd line where your desires may rest:
Th' insatiate miser ever is distress'd.
[tr. Howes (1845)]

The covetous man is ever in want; set a certain limit to your wishes.
[tr. Smart/Buckley (1853)]

The miser's always needy: draw a line
Within whose bound your wishes to confine.
[tr. Conington (1874)]

A miser's always poor. A bound assign
To what you want, then keep within the line.
[tr. Martin (1881)]

The avaricious man ever wants. Put a fixed limit on your desires.
[tr. Elgood (1893)]

The covetous is ever in want: aim at a fixed limit for your desires.
[tr. Fairclough (Loeb) (1926)]

The miser is always in need; draw a boundary line
Around your desires.
[tr. Palmer Bovie (1959)]

Greedy men are always poor: set limits to desire.
[tr. Fuchs (1977)]

The greedy never have enough: never want too much
For yourself.
[tr. Raffel (1983)]

The avaricious man always feels poor;
Set limits to what your desires make you long for.
[tr. Ferry (2001)]

The greedy are never content; fix an end to your longings.
[tr. Rudd (2005 ed.)]

The greedy always want: set fixed limits to longing.
[tr. Kline (2015)]