When I was about 10 years old, I took to heart Moroni's promise that, through prayer and sincere desire, I could ask God if the Book of Mormon is true, and get an answer.
I had enough siblings at the time that there was no place for real privacy in our house except the bathroom. So that's where I went. I locked the door and knelt to ask my Father if it were all true. And he answered! My whole body felt a surety of the truth of the Book of Mormon, along with a strong feeling of peace. I knew!
This was a beginning of my testimony of the gospel, and of my love for the scriptures. Before that day I believed what my parents and others had taught me, but from that day forth I know for myself.
And the catalyst for this event was a scripture - Moroni's promise from Moroni chapter 10.
Since then, every part of my testimony, whether it be about the church itself, modern and ancient prophets, or, the testimony central to the gospel - that of Christ and his atonement, have all either come to me originally through the scriptures or been strengthened by the scriptures.
I learned as a missionary that no action on the part of a gospel teacher or learner was as effective as getting the person to read the scriptures and pray about them. This the only really effective way to gain a testimony, at least for the vast majority of people.
There have been times and instances in my life where sorrow and worry were heavy on me. Nearly every time, when God has blessed me with relief from such, it has been through the scriptures. They bring the spirit of the Lord, and peace and comfort, as no other source has. Most often prayer is involved too. For example, early in Shana's illness, about the time she graduated from High School, I went to church fasting and praying for help. That day the first person to speak quoted D&C 101:16. I was reassured by the spirit when I heard this scripture, that all is, indeed, in God's hands, and we can trust Him to make all well in the eternal scheme of things.
I bear testimony that the scriptures have played a large part in making me what I am, in giving me my testimony, my gospel knowledge, and in comforting me in times of trial. Take for example, Isaiah 49:15-16. Christ can never forget our needs and is always mindful of us. That is perhaps the most comforting thought in all scripture.
What great blessings have come to me and to my family through these precious scriptures!
