The weekly Torah portion describes the inheritance rights of the firstborn:
“If a man has two wives, the one loved and the other unloved, and both the loved and the unloved have borne him children, and if the firstborn son belongs to the unloved, then on the day when he assigns his possessions as an inheritance to his sons, he may not treat the son of the loved as the firstborn in preference to the son of the unloved, who is the firstborn, but he shall acknowledge the firstborn, the son of the unloved, by giving him a double portion of all that he has, for he is the firstfruits of his strength. The right of the firstborn is his.” (Deuteronomy 21:15-18)
The original Hebrew word for ‘firstborn’ is ‘Bechor’ {בכר} which derives from the Hebrew root ‘B-Ch-R.’ {ב-כ-ר} From the Hebrew word for ‘firstborn’ – ‘Bechor’ – came the verb ‘Le-Veker’ {לבכר} which means ‘to prefer,’ to give preference to’ or ‘to favor’ and can be found in the English translation as ‘in preference to.’
This Hebrew term can be found in the Hebrew Bible when speaking about ‘first fruits’ which is ‘Bikurim’ {ביכורים} in the original Hebrew. Here, in the verses mentioned above, the Hebrew noun ‘Bechorah’ {בכורה} appears, and means ‘precedence.’
From this noun a Modern Hebrew adjective derived – ‘Bachi’r'{בכיר] – which means ‘senior’ and refers in many cases as a description of people in highly ranked positions.
According to a very interesting old Jewish tradition, the Hebrew Bible gave us a sign about the inheritance rights of the firstborn – which are DOUBLE – in the THREE original Hebrew letters of the word for ‘fristborn’ – ‘Bech’or’ – that are ‘Bet'{ב}, ‘Chaf'{כ} and ‘Resh’ {ר}. The sign is the special fact that for each of these three letters their numerical value is DOUBLE than the letter before them in the Hebrew alphabet.
‘Bet’ is ‘2’ and it is right after ‘Aleph’ {א} which is ‘1.’
‘Chaf’ is ’20’ and it is right after ‘Yod'{י} which is ’10.’
‘Resh’ is ‘200’ and it is right after ‘Kof'{ק} which is ‘100.’