Deuteronomy 25:15

15 Thou hast a stone complete and just, thou hast an ephah complete and just, so that they prolong thy days on the ground which Jehovah thy God is giving to thee;

Deuteronomy 25:15 Meaning and Commentary

Deuteronomy 25:15

[But] thou shall have a perfect and just weight, a perfect and
just measure shall thou have
That is, full weights, and full measures; and such as are alike, and everywhere used, according to the standard of the country; (See Gill on Leviticus 19:36);

that thy days may be lengthened in the land which the Lord thy God
giveth thee;
long life was always reckoned a blessing, and is frequently promised to, obedience, and particularly long life in the land of Canaan; which was a most delightful and fruitful land, and which a man might wish to live long in; deceitful men, are threatened with not living half their days, and such may they be said to be that use false weights and measures, ( Psalms 55:23 ) .

Deuteronomy 25:15 In-Context

13 `Thou hast not in thy bag a stone and a stone, a great and a small.

14 Thou hast not in thy house an ephah and an ephah, a great and a small.

15 Thou hast a stone complete and just, thou hast an ephah complete and just, so that they prolong thy days on the ground which Jehovah thy God is giving to thee;

16 for the abomination of Jehovah thy God [is] any one doing these things, any one doing iniquity.

17 `Remember that which Amalek hath done to thee in the way, in your going out from Egypt,