In the name of Allah, the all merciful, the most merciful.
Any who doubt the power of this phrase need only be reminded that it is the first ayah (verse) in the Qur’an. "When a human being who has a natural sentiment from Allah and considers Him a holy essence and a source of all Grace, begins an act in His name, it means that owing to His sanctity, nobility and greatness, the action becomes sacred."
(Shaheed Murtaza Mutahhari; Understanding the Noble Qur’an)
According to one hadith, Rasulullah (sallallahu ‘alayhi wasallam) was asked by Uthman (radiyallahu ‘anhu) regarding bismillah. He replied: "it is one of the great names of Allah (subhanahu wa ta’ala) and it brings a person as close to Allah (subhanahu wa ta’ala) as is the closeness of the whiteness and blackness of the eyes." [Tafsir Ibn Kathir]
[Al-Trimidhi 2/493]
Jabir (radiAllahu anhu) said: I heard the Messenger of Allah (PBUH) saying:
"If a person mentions the Name of Allah upon entering his house or eating, Satan says, addressing his followers: `You will find nowhere to spend the night and no dinner.' But if he enters without mentioning the Name of Allah, Satan says [To his followers]; 'You have found [A place] to spend the night in, and if he does not mention the Name of Allah at the time of eating, Satan says: 'You have found [A place] to spend the night in as well as food.'"
[Sahih Muslim 2/206]
Just by saying bismillah we will be able to carry out any action mentally and spiritually safeguarded from harm. We will be acting in the name of our Lord, the Most Merciful, Most Gracious, yielding a blissful result, insha'Allah!