Exactly 25 years ago this week, I said goodbye to my family and stepped into the Missionary Training Center in Provo to begin a mission for The Church of Jesus Christ of Latter-day Saints.

I was confident but nervous. Ready on the outside but totally terrified where it counts.

I had a testimony of the gospel of Jesus Christ, but it was greener than a lime.

I was Brazil bound — Belo Horizonte, to be exact — but likely to wait, like many young missionaries heading to that country, somewhere in the United States until my visa was processed.

I had two suitcases, crisp clothes and a new set of scriptures.

What I didn't have, and desperately wanted, was a letter from my father. He'd been gone three years, and though my siblings filled in beautifully, I still longed for a final pep talk from the man who taught me that it was fine to look up to him, but even better to look all the way up to Him with a capital H.

That was July of 1990.

This week, 25 years later, my family is saying goodbye to my oldest child, Oakli. She's stepping into the Missionary Training Center in Provo to begin a mission for The Church of Jesus Christ of Latter-day Saints.

She's confident but nervous. Ready on the outside but totally terrified where it counts.

She has a testimony of the gospel of Jesus Christ, and though it's got room to grow, it’s much less green than that 1990 lime of mine.

She's Brazil bound — Florianopolis, to be exact — but likely to wait, like many young missionaries heading to that country, somewhere in the United States until her visa is processed.

She has two suitcases, crisp clothes and a new set of scriptures.

And she's got one thing she might not even want, but she's taking anyway — a letter from her dad.

With a nod to my good friend Seth Adam Smith, author of the viral smash "Marriage Isn't for You," here’s an excerpt:

Hey Kiddo, guess what? A mission isn't for you.

Yes, because the Lord loves you, you'll benefit in ways you won't recognize until this life transitions into the one that never ends. You'll acquire new skills and sharpen others you've had since before we even knew you.

You'll become more converted and return a fantastic force for good. But any personal growth, the steps along your journey to conversion, those will come as a byproduct of serving him.

Never forget, the name at the bottom of the name tag is more important than the name at the top.

I'm so pleased you've decided to serve the Lord. Not because I would have been disappointed if you hadn't, but because you pondered, prayed and listened.

Then, when the Spirit invited you to serve, you said, “Yes.”

What more can a parent ask for?

If you had followed the same spiritual discovery pattern and didn't feel serving a mission was the Lord's will for you, and you listened and stayed home, I would've been equally thrilled.

I hope you know the road ahead will be the toughest you've ever walked. No matter how many times I tell you, or how often you hear stories from cousins, aunts, church leaders and teachers, you simply don't know the heartache that awaits.

Strangers will become dear friends faster than you can say the name of the church you represent.

They'll invite you into their home.

They will listen to you, pray with you and feed you the last crumbs from their cupboards.

Then, because they are blessed with the same agency you are, they'll ask you not to return.

The tears will flood your eyes before the door closes behind you.

Don't fight it. Let those feelings work on you, around you and through you.

It's good to be disappointed, even devastated when those you teach decide to distance themselves. But even when the visits stop, even when you no longer knock on their doors, keep knocking on their hearts.

Pray for them. Fast for them. Never, ever give up hope that one day, another missionary like you will sit on their couch and testify that truth has been restored. It only takes a single spark to reignite that righteous fire.

Speaking of prayer, invest many of them in your companions. They'll be different than you, but no less wonderful.

Some will be more knowledgeable, some less so.

Some more confident, others may struggle.

Many will teach with great power and authority, others with a soft, humble voice.

Celebrate and embrace those differences. God gives us all different talents, and as long as they all have arrows pointing to him, it doesn't matter what they look like.

Love them all. Serve them endlessly. Put the Savior first and your companion second. Do that, and you'll never be forgotten nor left behind by either one.

Be yourself. It's a common misperception that missionaries must flip a switch and become something from a handbook.

You're still you.

You still have a personality unique to you, just like the diverse personalities of your companions, and it will be the reason you connect with certain people and they connect with others.

Be yourself, but be the best version of yourself possible.

Be yourself, and trust the Holy Ghost will remind them of a relationship that predates your earthly blinders.

Treat every missionary like they're the finest you've ever met. Assume the best. Run from gossip like it's the most dangerous plague ever known.

Be obedient — at all times and in all places. If it’s the first law of heaven, it’s also the first law of a mission.

"Preach My Gospel" tells us the purpose of a missionary is to “Invite others to come unto Christ by helping them receive the restored gospel through faith in Jesus Christ and his Atonement, repentance, baptism, receiving the gift of the Holy Ghost and enduring to the end.”

Remember that first word: invite, invite and then invite some more.

No, a mission isn't for you. It's for those who haven't yet made baptismal covenants and those that follow. It's for the people who are waiting in other missions around the world to be taught five years from now by people you haven't even taught yet. Isn't that miraculous?

No, a mission isn't for you. It's for the Lord.

Child, I love you. I only wish you knew how much. The love parents have for children is impossible to describe because there simply aren't words for it.

I don't know. Maybe there are. God just hasn't given them to us yet.

Now get going! His mission awaits.

Jason Wright is a New York Times best-selling author of 10 books, including "Christmas Jars" and "The Wednesday Letters." Learn more at jasonfwright.com, or connect on Facebook at facebook.com/jfwbooks or by email at jwright@deseretnews.com.