Ephesians 1:11

in whom also we obtained a lot, having been predetermined according to the purpose of him who works all of us after the counsel of his will;
- Ephesians 1:11

in whom also we obtained a lot - "obtained a lot" is used to counter the false teaching in Ephesus that some believers in Christ would be excluded from receiving an inheritance in the Kingdom of God at the end of the age.

When the Israelites conquered Canaan, it was divided by lot and given to the tribes. Ezekiel describes the land that is to be divided by lot when the Messiah will come to reign over the earth.

Ezekiel 48:29
This is the land which you shall divide by lot to the tribes of Israel for inheritance, and these are their several portions, says the Lord Yahweh.

having been predetermined - "predetermined" is often translated "predestined". This again is related to the inheritance of the land. In the Septuagint the word for "boundary" or "border" is "horizo" in the Greek:

Joshua 18:20
The Jordan was its border (horizo) on the east quarter. This was the inheritance of the children of Benjamin, by the borders around it, according to their families.

The word that Paul uses for "predetermined" is "pre-horizo". In other words, Paul was saying that believers in Christ had been given an inheritance before any land boundaries had been established.

according to the purpose of him who works all of us after the counsel of his will