Gemara: Rav Huna said in the name of Rabbi Meir, and so was stated in the name of Rabbi Akiva: A person should always be used to saying, "All that is done from the Heavens is for the good." This is exemplified by the story of Rabbi Akiva. Rabbi Akiva was going on the way, and he had with him a donkey, a rooster, and a light. He came to a town and looked for a place of lodging but was turned down. He said: "All that is done from the Heavens is for the good." He went and slept in the wild. A lion came and ate the donkey. A cat came and ate the rooster. A wind came and blew out the light. He said: "All that is done from the Heavens is for the good." At night, a band of criminals came and captured the people of the town. He said: "That is why we say, ‘All that is done from the Heavens is for the good.’"

Ein Ayah: [In previous pieces, we saw what someone should think positively while reciting the blessing for bad things that occurred.] A statement is more individually oriented and more external than an internal thought. When a person gets used to saying, "All that is done from the Heavens is for the good," it will have an effect on the more inclusive and internal. In practice, as well, while the idea that everything is for the good relates to the collective [for sometimes the individual suffers for the benefit of the collective], the sense of security that it spawns can elevate an individual to the level of the collective.
[Let us now analyze the details of the story involving Rabbi Akiva.] There are various ways in which apparently bad things can come to a person. One way is by means of another person, who has free choice to either do bad or refuse to do good for his counterpart. Secondly, an animal, which is driven by his own needs, can cause damage to a person. Finally, some inanimate natural force can wreak havoc on a person in a very specific way that is precisely ordained from Above.
Each of these categories is found in Rabbi Akiva’s story and through them all Rabbi Akiva was actually saved from the captors who came to the town. The people of the town made the ostensibly harmful and cold-hearted decision to not allow Rabbi Akiva a place of lodging. The lion killed the donkey as it is apt to do, in a manner that deprived Rabbi Akiva of the source of transportation he needed, and the cat killed the rooster, which Rabbi Akiva needed for spiritual reasons (to get up early for Torah study and prayer). These too turned out to help save Rabbi Akiva through Divine Providence especially as it relates to those who fear Hashem. The final, apparently negative element was the blowing out of the candle. The loss of light, which brings happiness to the heart and soul, also turned out to be positive.
This story teaches us that one should not be overly perturbed when things seem to not go well, whether he is afflicted by human adversaries or by other means, and whether it affects him in the realm of worthy physical needs or spiritual ones. Everything is planned by Hashem in a complicated manner that, at the end, will bring about his salvation. If a person has a positive outlook on that which is happening to him, he can remain in good spirits, which can bring him better success in matters of Torah, knowledge, and fear of Hashem.