1 Nephi 2

Looking back, Nephi remembers -

"...I, Nephi, being exceedingly young, nevertheless being large in stature, and also having great desires to know of the mysteries of God, wherefore, I did cry unto the Lord; and behold he did visit me, and did soften my heart that I did believe all the words which had been spoken by my father..."  (1 Nephi 2:16)

What rang true to me was "I did cry unto the Lord; and behold he did visit me, and did soften my heart".  I believe that this simple experience is how many receive a testimony of Jesus Christ.  That is humbly approaching the Lord and finding their hearts softened.

It reminds me of Alma's analogy -

"Now, if ye give place, that a seed may be planted in your heart, behold, if it be a true seed, or a good seed, if ye do not cast it out by your unbelief, that ye will resist the Spirit of the Lord, behold, it will begin to swell within your breasts; and when you feel these swelling motions, ye will begin to say within yourselves—It must needs be that this is a good seed, or that the word is good, for it beginneth to enlarge my soul; yea, it beginneth to enlighten my understanding, yea, it beginneth to be delicious to me."  (Alma 32:28)