1 Nephi 6:6 - 1 Nephi 7:4

1 Nephi 6:6 Wherefore, I shall give commandment unto my seed, that they shall not occupy these plates with things which are not of worth unto the children of men.

Nephi knowing how worthless the philosophies of men are and sees absolutely no reason to record the worthless ideas men have come up with. His record is not to become an history of philosophies. He only wants to record spiritual things that will help one to gain or increase in his testimony of Christ.

1 Nephi 7:1 And now I would that ye might know, that after my father, Lehi, had made an end of prophesying concerning his seed, it came to pass that the Lord spake unto him again, saying that it was not meet for him, Lehi, that he should take his family into the wilderness alone; but that his sons should take daughters to wife, that they might raise up seed unto the Lord in the land of promise.

After Lehi finishes up his prophecies of what will happen to his descendents, he told his sons to again return to Jerusalem for wives. For if there were no wives of the boys or husbands for their sisters, there would be no descendents that would fulfill the prophecies.

1 Nephi 7:2 And it came to pass that the Lord commanded him that I, Nephi, and my brethren, should again return unto the land of Jerusalem, and bring down Ishmael and his family into the wilderness.

Lehi specifically tells the boys to bring down a particular family into the desert. Lehi must have had some acquaintance with them or at least knew from revelation that Ishmael’s family and his children would fulfill the requirements for spouses for Lehi’s children.

1 Nephi 7:3 And it came to pass that I, Nephi, did again, with my brethren, go forth into the wilderness to go up to Jerusalem.

Nephi and his brothers once again return to Jerusalem. This time to get wives. Wonder if the older boys had objections this time to this excursion unto keeping a commandment of the Lord?

1 Nephi 7:4 And it came to pass that we went up unto the house of Ishmael, and we did gain favor in the sight of Ishmael, insomuch that we did speak unto him the words of the Lord.

The boys head for Ishmael’s home and reveal their mission to him and his family. Nephi uses testimony to convince Ishmael to join Lehi and his family. Nephi undoubtedly gave his personal testimony of what he and his father saw in visions. And if Ishmael's family knew Lehi well and Lehi's personal integrity, they had to give Nephi's testimony more than just a listening.

I think here is the basis for convincing people of your convictions. Use testimony not argument. In experience shown me that for any argument there is a counter argument. Look at debates and debate contests. People can be given any topic and can come with arguments to support any side.

I am sure that Nephi could have come with any number of arguments to show why it was imperative for Ishmael and his family to get out of Jerusalem, but it was testimony that won the family over. There is no arguing with testimony. It is up to the hearer to either except or reject it. That was what faced Ishmael. Ishmael chose to accept Nephi's testimony.

Arguing is a waste of time. It usually causes people to be more entrenched in their positions. We see this continually in political debate. It is better to just state your position and answer questions rather than debate. Debate causes contention which the Book of Mormon tells us is inspired by satan.