Exodus 4:23

And I say
<0559> (8799)

unto thee, Let my son
<01121>

go
<07971> (8761)_,

that he may serve
<05647> (8799)

me: and if thou refuse
<03985> (8762)

to let him go
<07971> (8763)_,

behold, I will slay
<02026> (8802)

thy son
<01121>_,

[even] thy firstborn
<01060>_.

Exodus 11:5

And all the firstborn
<01060>

in the land
<0776>

of Egypt
<04714>

shall die
<04191> (8804)_,

from the firstborn
<01060>

of Pharaoh
<06547>

that sitteth
<03427> (8802)

upon his throne
<03678>_,

even unto the firstborn
<01060>

of the maidservant
<08198>

that [is] behind
<0310>

the mill
<07347>_;

and all the firstborn
<01060>

of beasts
<0929>_.