We are all accustomed to seeing tall claims in advertise ments:

Intelligent customers always look for that small asterix (*) sign, because this is where all the reality lies.
No doubt it is a clever advertising ploy, but it works for sure. If one comes across such a sweeping, tall claim from the Supreme Lord Himself, do we try to search out that small asterix?
In the Bhagavad gita Lord Krsna assures Arjuna that He will protect him from all fears – ma sucah [Bhagavad gita 18.66] What exactly do we fear?
Loss of health, disease, ignorance, destruction of property, death. There are innumerable causes of fear.
In the Srimad Bhagavatam, the great sage Narada Muni advises King Citraketu "My dear King, now you are actually experiencing the misery of a person who has sons and daughters. 0 King, owner of the state of Surasena, one's wife, his house, the opulence of his kingdom, and his various other opulences and objects of sense perception are all the same in that they are temporary. One's kingdom, military power, treasury, servants, ministers, friends and relatives are all causes of fear, illusion, lamentation and distress. They are like a gandharva nagara, a nonexistent palace that one imagines to exist in the forest. Because they are impermanent, they are no better than illusions, dreams and mental concoctions."
The Srimad Bhagavatam further explains that fear arises due to a "dvitiya" or the misconception of a "second" power.
This is called "maya" or illusion. The one reality is Krsna and maya is secondary. Just like light and darkness. Darkness is not first; light is first. Darkness has no separate existence it is simply absence of light. Real existence is light. The whole creation can be compared to the sun. When the sun is covered by a cloud, it is called darkness. If you rise above the cloud, you come to sunshine. It may be dark when you take off from a plane on the ground, but when you go seven miles above, then you see there is sunlight. Again, if you fly in a plane in the morning and go in the western direction, you will never see night. Sometimes we take off at ten o'clock, and go westwards. Then, after few hours, we see it is still ten o'clock, and the light is there. This is our practical experience.
Ignorance is the cause of sinful life and it results in misery and suffering which causes fear psychosis. Distress has three causes sin, material desires and ignorance. Srila Rupa Goswami explains that devotional service unto Lord Krsna is the best means to obtain relief from distress because it is the only process that can counteract all the three causes.
Sin – Sinful actions produce two reactions : Manifest and Unmanifest. A disease caught early is curable, but is far more difficult to eradicate if allowed to become chronic. Similarly, sinful reactions are more difficult to eradicate once they become manifest. Unmanifest reactions are also of two types – one type creates direct physical or emotional suffering and the oth er creates indirect suffering by increasing our sinful proclivities. For example, if we engage in illicit sex, we receive two types of reactions. One type creates some direct physical or emotional suffering. The other creates suffering by exacerbating our proclivity for sex, thereby increasing sexual desires, impelling future illicit sex, and entangling us in a karmic cycle of suffering.
Sinful Desire – The Srimad Bhiigavatam (6.2.17) explains that many processes can neutralize the reactions of sinful activities, but only devotional service can uproot sinful desire.
Ignorance – The root cause of suffering is ignorance of our true identity as Krsna's eternal servant. In ignorance, we act as an enjoyer and suffer the concomitant reactions. As long as one is ignorant about his identity, he is sure to act wrongly and thereby become entangled in material contamination. Therefore the Padma Purana declares "Pure devotional service in Krsna consciousness is the highest enlightenment which is just like a blazing fire. This fire kills all the inauspicious snakes of material desires".
Finally, here is Srila Prabhupada's assurance about the protection given by Lord Krsna – One should be attracted by the beautiful vision of Krsna. His name is Krsna because He is all attractive. One who becomes attracted by the beautiful, all powerful, omnipotent vision of Krsna is fortunate. There are different kinds of transcenden talists some of them are attached to the impersonal Brahman vision, some of them are attracted by the Supersoul feature etc., but one who is attracted to the personal feature of the Supreme Personality of Godhead, and, above all, one who is attracted by the Supreme Personality of Godhead as Krsna Himself, is the most perfect transcendentalist. In other words, devotional service to Krsna, in full consciousness, is the most confidential part of knowledge, and this is the essence of the whole Bhagavad-gita. Kannayogis, empiric philosophers, mystics and devotees are all called transcendentalists, but one who is a pure devotee is the best of all. The particular words used here, ma sucah, "Don't fear, don't hesitate, don't worry," are very significant. One may be perplexed as to how one can give up all kinds of religious forms and simply surrender unto Krsna, but such worry is useless.
(Syamananda Dasa)