“Cʟᴏsɪɴɢ ᴛʜᴇ Gᴀᴛᴇ ᴛᴏ ᴛʜᴇ Lᴏᴡᴇʀ Rᴇᴀʟᴍs”
Mᴀsᴛᴇʀ Aᴄʜᴀʀᴀᴠᴀᴅᴇᴇ Wᴏɴɢsᴀᴋᴏɴ

Closing the gate to the lower realms (Apāyabhūmi) means attaining the first stage of enlightenment. One who reaches this stage is called Sotāpanna (stream-enterer). This is a primary wish of Dhamma practitioners as most of them think that Nirvana is far beyond their destiny. Therefore, “Attaining just the stage of Sotāpanna” is a highly possible wish for them. This is also the wish of most moral people although they do not practice meditation. Some even try to take shortcuts such as chanting, worshiping holy objects, or doing small good deeds and expect to attain the stage of Sotāpanna.

What is the relation between being Sotāpanna and closing the gate to the lower realms?
The lower realms are the states in which souls can be reborn: hell beings, hungry ghosts (Peta), angry demons (Asurakaya), and animals. Attaining the first stage of enlightenment or becoming Sotāpanna guarantees that one will not be reborn in these stages of misery. Thus, he can be reborn as celestial being or human. And if he is reborn as human, he will only be reborn not more than 7 lifetimes in order to reach the enlightenment, becoming an Arahant. Therefore, attaining the stage of Sotāpanna means closing the gate to these realms of misery.

Closing the gate to the lower realms is an attainment in the mind level. One cannot achieve it by reading Dhamma books or doing certain good deeds, then assuming that he has reached that stage. In fact, that is still far away from the fruition. If, especially, the person does not perfectly observe the precepts, there is no reason to think about Sotāpanna attainment.
Moreover, how many lives one has been reborn? How much sin and unwholesomeness one has accumulated? In fact, one should realize by himself what kind of deeds he has done in this life. And how about countless deeds that he cannot realize? How could it be possible to close the gate to the lower realms with only little effort? Therefore, if one wishes to be a Sotāpanna, he must practice Vipassana meditation.

If someone persuades you to do many things, such as tremendous chanting without practicing concentration and mindfulness meditation and without observing precepts perfectly, and says that you will be able to attain the enlightenment and reach Nirvana in the end…then you must contemplate carefully. How would any actions not in line with the Buddha’s core teaching enable one to achieve that? Would there be anyone wiser than the Buddha? You have to thoroughly think about it.

Source: An excerpt from “What is the Closure of Gate to Apayabhumi (States of Misery)? How is it important?” FB: 5000s ข้ามห้วงมหรรณพ กับ อ.อัจฉราวดี วงศ์สกล November 17, 2019

Quote
Closing the gate to the lower realms (Apāyabhūmi) is an attainment in the mind level.
One cannot achieve it by reading Dhamma books or doing certain good deeds, then assuming that he has reached the stage of enlightenment.
If one wishes to close the gate to the lower realms, to be a Sotāpanna, he must practice Vipassana meditation.

Translator: Chotika Rujirachun, Supravee Veerapala, Patcharanan Laopimolpan, Wisuwat Sutthakorn

Please see full article at
https://www.techovipassana.org/post/closing-the-gate-en