Ephesians 2:12

that at that time ye were without all knowledge of the Messiah, being aliens from the common-wealth of Israel, and strangers to the covenants of promise, having no hope, and living in the world without any true knowledge of God.

1 John 5:18

we know that a true christian will not commit such a sin, for he that is the child of God keeps upon his guard, so that the wicked spirit does not approach him.

Treasury of Scripture Knowledge

Summary

Neither from a stranger's hand shall ye offer the bread of your God of any of these; because their corruption is in them, and blemishes be in them: they shall not be accepted for you.

Bible References

Because

Ephesians 2:12
that at that time ye were without all knowledge of the Messiah, being aliens from the common-wealth of Israel, and strangers to the covenants of promise, having no hope, and living in the world without any true knowledge of God.
1 John 5:18
we know that a true christian will not commit such a sin, for he that is the child of God keeps upon his guard, so that the wicked spirit does not approach him.