Exodus 30:12-14

12 a“When you take the census of the people of Israel, then each shall give ba ransom for his life to the Lord when you number them, that there be no plague among them when you number them. 13Each one who is numbered in the census shall give this: half a shekel
A  shekel was about 2/5 ounce or 11 grams
according to the dshekel of the sanctuary (the eshekel is twenty gerahs),
A  gerah was about 1/50 ounce or 0.6 gram
ghalf a shekel as an offering to the Lord.
14Everyone who is numbered in the census, from twenty years old and upward, shall give the Lord’s offering.
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