[DouglasKC]

"We are destined to be sons and daughters of God"
Who is your "we"? Are all men destined to be the sons and daughters of God ? If not, then to what are the others destined ?

All who have chosen to believe are destined to become sons and daughters of God. The others are destined to death.

[Jerry_M]

"All who have chosen to believe are destined to become sons and daughters of God. The others are destined to death."

I would modify your sentence slightly:

All who were chosen (by God) to believe are destined to become sons and daughters of God. The others are destined to death.