According to Dr Sharib:-

"According to some of the 'ulema' al-Mu'min is the One Who gives
safety and shelter to the people in this world as well as in the world

"To emulate this name you should abstain from inflicting injury on the
people or in any way ignore their welfare."

He tells us that appropriate recitation will free the person from fear, and
secure safety for life and property.

It can also make people obedient to you but it must be used only for just

see 'The 99 Most Beautiful Names of Allah' by Dr Zahurul Hassan Sharib

Some other references:

The holy Prophet Muhammed said:

'When one believes in the last day, his neighbour is safe from his

Hadith (Muslim)

Al-Ghazali seems to imply that God gives both the cause of fear and the
means of protection from that fear. As an example he suggests that the
man with one arm uses the other arm to protect himself from falling. He
further says:
Then there is his [man's] greatest fear - of eternal damnation - and
nothing will protect him from that but the profession of faith in the unity of
God...... He [God] says ' "there is no god but God" is My fortress, and
whoever enters into my fortress is safe from My punishment.'

"For there is no safety in the world unless it be derived from intermediaries
which He alone creates and guides us in using. For He is the one who "gave
unto each thing its nature and then guided it aright" (Qur'an 20:50). He is truly
the absolutely faithful one."

(Al-Ghazali - The Ninety-nine Beautiful Names of God. Trans. Burrel/Daher: ITS: 1992.)

Khawaja Muinuddin Hasan Chishti says:

"When passing from 'there is no god but God' you reach God, you then
reach the coveted station and will become a mumin (a believer)."

( from 'The Meditations of Khawaja Muinuddin Hasan Chishti. Sharib Press. 1994)
Bismillah ir Rehman ir Rahim
The Guardian of Faith, The Author of Safety and
Security, The Giver of Faith, The Faithful,
The Protector
Qur'an 59:23
Allah is He, than Whom
There is no other god:-
The Sovereign, the Holy One,
The Source of Peace (and Perfection),
The Guardian of Faith,
The Preserver of Safety,
The Exalted in Might,
The Irresistible, the Supreme.
Glory to Allah!
(High is He)
Above the partners
They attribute to Him.
Huwallaa-hullazii Laaa-'illaaha 'illaa
Huu; - 'Al-Malikul-Qudduusus -
Salaamal - 'Mu'minul - Muhay-minul -
'Aziizul - Jabbaarul-Mutakabbir:
Subhaanallaahi 'ammaa yushrikuun.

(Qur'an 59:23 trans Y. Ali)
Only those are Believers
Who have believed in Allah
And His Apostle, and have
Never since doubted, but
Have striven with their
Belongings and their persons
In the Cause of Allah:
Such are the sincere ones.
'Innamal - Mu'-minuunal -
laziina 'aamanuu billaahi wa
Rasuulihii summa lam
yartaa-buu wa jaahaduu bi-
'amwaali - him wa'anfusihim
fii Sabiilillaah: 'ulaaa - 'ika
humus - Saadiquun.

(Qur'an 49:15 trans Y. Ali)