Romans 8:29

For whom he foreknew, he also predestinated to be conformed to the likeness of his Son, that he may be a first-born among many brothers;

Hebrews 12:23

and to the church of the first-born who are enrolled in heaven, and to a judge the God of all, and to spirits of the righteous made perfect,

Treasury of Scripture Knowledge

Summary

All the firstling males that come of thy herd and of thy flock thou shalt sanctify unto the LORD thy God: thou shalt do no work with the firstling of thy bullock, nor shear the firstling of thy sheep.

The firstling

Bible References

The firstling

Romans 8:29
For whom he foreknew, he also predestinated to be conformed to the likeness of his Son, that he may be a first-born among many brothers;
Hebrews 12:23
and to the church of the first-born who are enrolled in heaven, and to a judge the God of all, and to spirits of the righteous made perfect,