Q: How do angels interact with humans? 

A: I answer this question in my book, The Non-Prophet’s Guide to Spiritual Warfare.

Here is an excerpt:

We discover in other portions of Scripture that angels can enter—and interact with—our physical realm. We find them eating meals with humans (Genesis 18:7-8), fighting (2 Kings 19:35), and grabbing humans by the hand (Genesis 19:16). Hebrews 13:2 even states that some people have interacted with angels without even realizing they were not human. [Verse: Hebrews 13:2—Do not forget to show hospitality to strangers, for by so doing some people have shown hospitality to angels without knowing it.]

The Bible does indicate that believers in Christ (and/or possibly small children) have guardian angels (Matthew 18:10). We don’t know whether this system of protection is set up as a man-to-man or zone defense, but verses such as Hebrews 1:14 also seems to support the notion. We read that verse in a previous chapter but it is worth reading again. The verse reads, “Are not all angels ministering spirits sent to serve those who will inherit salvation?” It is humbling to think that just beyond the veil—and possibly in our physical reality—angels are tasked with protecting and ministering to those know Christ as Savior.

While angels are tasked with serving God and carrying out his redemptive plans for mankind, fallen angels attempt to thwart God’s plans and they submit to the direction of Satan, the highest ranking fallen angel (as discussed above). The fallen beings in the unseen realm are called fallen angels, demons, or unclean spirits.

A demon/unclean spirit can influence or even inhabit people who are not born-again believers in Christ. When someone accepts Christ as Savior, they are indwelled (and sealed) by the Holy Spirit. A demon cannot occupy the person who is sealed and protected by the presence of the Holy Spirit. Some theologians assert that demons and fallen angels are different types of evil beings. I talk more about that in my book, The Non-Prophet’s Guide to Spiritual Warfare.