He starts off his account by explaining that he was raised in the gospel by a good man: "Behold, it came to pass that I, Enos, knowing my father that he was a just man—for he taught me in his language, and also in the nurture and admonition of the Lord...".
I, like Enos, was raised by great parents. They tried to raise me up unto the Lord. They instilled in me the importance of reading the scriptures, praying, attending church meetings, being a kind person, and everything else a good parent would. Even with my parents as a great example, I began to question the truthfulness of the gospel. Enos, similarly, had this experience. He says, "And I will tell you of the wrestle which I had before God...and the words which I had often heard my father speak concerning eternal life, and the joy of the saints, sunk deep into my heart...And my soul hungered."
To find out the truth for himself, Enos prayed. He didn't just pray, but prayed ALL DAY LONG! "I kneeled down before my Maker, and I cried unto him in mighty prayer and supplication for mine own soul; and all the day long did I cry unto him; yea, and when the night came I did still raise my voice high that it reached the heavens."
At last, He received the confirmation he was looking for. Now, many of the stories in The Book of Mormon end up with incredible reasons why they believe. Sometimes it is heavenly messengers. Sometimes the Lord sends them trials that humbles them. In Enos' story, this doesn't seem to be the case. He accounts, "And there came a voice unto me, saying: Enos, thy sins are forgiven thee, and thou shalt be blessed. And I, Enos, knew that God could not lie." It was as simple as a voice coming to him and confirming to his heart.
My own story is the same, although I didn't pray all day long. It took reading the scriptures everyday. I had to learn how to pray everyday. By doing these simple things, I was able to gain a relationship with my Heavenly Father. Over time, I was able to feel the truthfulness of the gospel. It wasn't a grand experience that led me to believe. It was simple confirmation to my heart. When the confirmation came to me, I felt like Enos did when he said, "And after I, Enos, had heard these words, my faith began to be unshaken in the Lord."
It is my testimony that we can know the truth for ourselves. We can follow the example of Enos and pray to our Heavenly Father. Enos did WORK to be able to learn of the truth. He had to pray all day and into the night before he gained an answer. I know that if we put in the work (read the scriptures, pray, attend church meetings), we can gain a testimony that it is true for ourselves. Then our faith will be unshakeable like Enos!