Summary: There has been a dramatic increase in the number of those who say they are experiencing angelic visitations as a result of open heavenly "portals"
Starting before the turn of the 20th century, and continuing on through to the present time, there has been a dramatic increase in the number of those who say they are experiencing angelic visitations as a result of heavenly "portals" (doorways/gates/windows) opening up in various locations around the world where angels ascend and descend.
It is truth that God can choose to sovereignly send an angel from Heaven. These types of events are recorded in Scripture and should not be dismissed as imaginary or purely demonic. However, there is a danger when intentionally looking for "portals" because it is primarily a pagan practice dating back thousands of years that has been warmly embraced by the Occult. Jesus warned that there is a "portal" many will enter that is wide, and the path to it is "broad." Yet, He said it "leads to destruction" (Matt 7:13 NIV). Jesus also said that there is a small "portal" and a "narrow" path "that leads to life, and only a few find it" (Matt 7:13-14 NIV).
What Are Gates in the Bible?
Old Testament Usage
In Hebrew, the word "petach" is a noun and is used for "doorway; opening; entrance; gate(s)." It represents the "opening through which one enters a building, tent, tower (fortress), or city" (see Gen 18:1, 19:6; Gen 38:14, 43:19; Ex 35:15). It was both a place to sit and an opening for entry. It is also used figuratively by the Prophet Micah (vs7:5) regarding the low morality of the people when he advised them to trust no one, telling them to guard their lips (literally, the "openings" of their mouths). It is can also refer to the human heart as a house or building with the devil crouching at the "entrance," ready to subdue it utterly and destroy its occupant (Gen 4:7).
The Hebrew word "palach" is a verb meaning "to open" and has an extended meaning "to cause to flow," "to offer for sale," "to conquer," "to surrender," "to draw a sword," "to solve [a riddle]," "to free."
Another Hebrew Word translated as ‘door’ is “petrach,” and is used to refer to the door of a chamber in which people hide; door(s) of house (rooms) distinguished from door-way (compare 1 Kings 6:31); a temple (1 Kings 6:34, 7:50; 2 Kings 18:16; 1 Chron 22:3; 2 Chron 3:7; 4:22; 28:24; 29:3; Neh 6:10; Mal 1:10; so of Ezekiel's temple, Ezek 41:23,24; 41:25); gates of city (Deut 3:5; Josh 6:26)
New Testament Usage
The Greek word "thura" is translated as 'door, gate' and is used literally (Matt 6:6; 27:60), and metaphorically of Jesus (John 10:7,9); of faith by acceptance of the Gospel (Acts 14:27); of "openings" for preaching and teaching the Word of God (1 Cor 16:9; 2 Cor 2:12; Col 4:3; Rev 3:8); of "entrance" into the Kingdom of God (Matt 25:10; Luke 13:24-25); of Jesus "entrance" into a person when they become Born-Again (Rev 3:20); of the nearness of Jesus second coming (Matt 24:33; Mark 13:29; James 5:9), and of "access" to behold visions relative to the purposes of God (Rev 4:1).
Another Greek word that is translated as 'gate' is "pule," and is used: literally for a large "gate" in the wall, either of a city or palace or temple (Luke 7:12; Acts 3:10; 9:24; 12:10; Heb 13:12); metaphorically, of the "gates" at the entrances of the ways leading to life and to destruction (Matt 7:13,14); of the "gates" of Hades (Matt 16:18). The importance and strength of "gates" made them viewed as synonymous with power. By metonymy, the "gates" stood for those who held government and administered justice there.
Watchers at the Gates
"And now, O sons, listen to me: blessed are those who keep my ways. Hear instruction and be wise, and do not neglect it. Blessed is the one who listens to me, watching daily at my gates waiting beside my doors. For whoever finds me finds life and obtains favor from the Lord, but he who fails to find me injures himself; all who hate me love death." (Prov 8:32-36 ESV)
Watching daily at the gates (Heb: "deleth" = gate/door) is figurative language that can refer to: a student waiting for the doors of a school to open so they can begin their studies; a servant of a King expecting the appearance of his sovereign; Levites guarding the doors of the temple, or a person waiting for their lover.
Jacob, the grandson of Abraham, was fleeing from his twin brother Esau, who had promised to kill him. On the way to his relative's house, Jacob laid down for the night. As he was dreaming, he saw a ladder between Heaven and Earth. God's angels were on it, ascending and descending.
"And he dreamed, and behold a ladder set up on the earth, and the top of it reached to heaven: and behold the angels of God ascending and descending on it." (Gen. 28:12 KJV)