Do dead believers watch over us?
Do ancestors/ believers in Heaven have anything to do with Earthly things anymore, like do they watch over us or protect us? What's so different from believing that and of guardian angels protect us from within Heaven?
And relatedly, does Scripture teach that when believers die they automatically go to Heaven?
A: When we die Scripture says we are in the presence of the Lord, in Heaven.
Scripture notes we have an angel assigned to us "until salvation" which might mean until we get saved or until the Day of Salvation [the day which is like Judgment Day for the lost is the Day of separating believers from unsaved]. They only do as God says. We do not talk to nor worship them. We cant even see them.
There's a misunderstanding out there by some and teach incorrectly that people remain in the grave until Judgment Day. Which btw would then negate the idea they watch over us from heaven.
Believer's today are in Heaven. There was 2 sides to the place of the dead; Sheol. One side is Hell and beyond the chasm was Paradise. Paradise is where believers were until Christ arrived there. When He rose from the grave Scripture noted He set the captives free. Those who were in Paradise rose (behind) after Him. They were seen by many in the town and then were gone. Jesus took them to Heaven. In Revelation we see myrtered believers there asking God how long till their death is avenged. We also see verses telling us that when we are absent from the body we are present with the Lord. And that in Heaven our tears are wiped away, the former things are passed ... we no longer have a connection to earth; our eternity has begun. These are straight from Scripture.
The ones who died are in the eternal relm, believers are living eternal life there awaiting the Last Day of humanity when all believers will be ushered completely together into eternity >> to the new Heaven and new Earth. Between then and now, they have nothing to do with this sin stained world anymore. They dont watch over us. God does. God always and only does. Scripture reveals this in many places.
It would be a good idea to read through the 66 books of Scripture (cover to cover) and look for where these things are revealed, as a personal study.
Here's some additional resources
On the cloud of witnesses
When all Church era believers are (finally all gathered) in Heaven (from the the Rapture), God will allow us to see His Judgment unfolding on earth. Explained here. They don't watch over anyone, they watch the Tribulation... and then return with Christ to reign [then the unfolding of the rest of end times happens]. The End. New Beginning.