1 Nephi 3 - 5

Lehi tells his sons -

"...the Lord hath commanded me that thou and thy brothers should go unto the house of Laban, and seek the records, and bring them down hither into the wilderness." (Book of Mormon 1 Nephi 3:4)

To which Nephi responds in great faith -

"...I will go and do the things which the Lord hath commanded, for I know that the Lord giveth no commandments unto the children of men, save he shall prepare a way for them that they may accomplish the thing which he commandeth them." (Book of Mormon 1 Nephi 3:7)

While Laman and Lemuel -

"...murmur, saying it is a hard thing which I have required of them..." (Book of Mormon 1 Nephi 3:5)

But nonetheless, they join with Nephi and Sam took their journey back to Jerusalem. And after casting lots -

"...the lot fell upon Laman; and Laman went in unto the house of Laban, and he talked with him as he sat in his house.
12 And he desired of Laban the records which were engraven upon the plates of brass...and behold, it came to pass that Laban was angry, and thrust him out from his presence; and he would not that he should have the records. Wherefore, he said unto him: Behold thou art a robber, and I will slay thee.
14 But Laman fled out of his presence... (Book of Mormon 1 Nephi 3:11 - 14)

And after relating what happened to his brothers, they -

"...began to be exceedingly sorrowful, and...were about to return unto [their] father in the wilderness." (Book of Mormon 1 Nephi 3:14)

A think there are some great lessons to learned here, not only in spiritual matters, but also in our temporal day to day lives. The tendency of many people is as soon as they encounter a major obstacle or wall, they give up, they throw their hands up and say they tried, that's it, and there's nothing else they could have possibly done - no persaverance, no re-thinking, no consideration of alternate approaches, etc. I did my job. I did the best I could do! In this case, Laban said "No". But Nephi didn't let that stop him. He had been given a job to do, in this case a commandment, and he would not give up until he had accomplished it. Nephi comes up with another idea -

"...let us be faithful in keeping the commandments of the Lord; therefore let us go down to the land of our father's inheritance, for behold he left gold and silver, and all manner of riches." (Book of Mormon 1 Nephi 3:16)

So they -

"...went down to the land of our inheritance, and we did gather together our gold, and our silver, and our precious things.
23 And after we had gathered these things together, we went up again unto the house of Laban.
24 And it came to pass that we went in unto Laban, and desired him that he would give unto us the records which were engraven upon the plates of brass, for which we would give unto him our gold, and our silver, and all our precious things." (Book of Mormon 1 Nephi 3:22 - 24)

Again they failed for -

"...when Laban saw our property, and that it was exceedingly great, he did lust after it, insomuch that he thrust us out, and sent his servants to slay us, that he might obtain our property.
26 And it came to pass that we did flee before the servants of Laban, and we were obliged to leave behind our property, and it fell into the hands of Laban." (Book of Mormon 1 Nephi 3:25 - 26)

At this point, Laman and Lemuel were done. What more could the Lord really expect of them more? Nephi was persistent. Because of his faith and commitment, he wouldn't give up. The third time, Nephi tells us that on his own, he -

"...crept into the city and went forth towards the house of Laban.
6 And I was led by the Spirit, not knowing beforehand the things which I should do." (Book of Mormon 1 Nephi 4:5 - 6)

And because of his faith and persaverance, the blessed him and provided the way for him to accomplish that which he was commanded and -

"...took the plates of brass ...and departed into the wilderness, and journeyed unto the tent of our father." (Book of Mormon 1 Nephi 4:38)

Another important lesson that should be commented on is that just because the Lord has given a commandment does not mean that he has an obligation to make easy to accomplish. It seems that in regards to the commandments of the Lord, the success or blessings, only come -

"...after the trial of your faith." (Book of Mormon Ether 12:6)

The difference between a valiant servant and a mediocre servant many times lies in the persistence and faith of the servant.