How Do You Get Confidence? Joel Osteen's Advice (VIDEO)

If you want to know what you're going to be like in five years, Pastor Joel Osteen says, you should listen to what you're saying about yourself right now after you utter the words "I am."

"When you speak that out, you're setting the tone for your life," Pastor Osteen told Oprah in an episode of "Oprah's Lifeclass ."

Oprah says she had "a big aha!" after hearing a sermon Pastor Osteen preached at his Lakewood Church in Houston . In it, he warned: "Whatever follows 'I am' is going to come looking for you."

Pastor Osteen says it's the little things that keep most people back -- and at times, your own words can be defeating instead of encouraging.

"You can't go around saying all day, 'I'm not attractive, I'll never get any good breaks, I'm a lousy mother,' he says. "That's just going to draw in negative [thinking and] defeat -- things that are going to keep you from God's best."

Oprah says she recently caught herself complaining about being tired while on the set of filming the movie "The Butler ," and was reminded of Pastor Osteen's sermon. "For me, I can't immediately go to 'I am so energized,' because I wasn't," she says. "So I started to say, 'I am looking forward to my second wind.' And it came!"

In this clip, Pastor Osteen tells Oprah that words can give a clue as to how you feel about yourself. For example, he says, "Ladies, when you say 'I am beautiful,' you know what you're doing? You're inviting beauty to come in. You're inviting wholeness and freshness and vitality."

So how can you speak words that promote a positive destiny? Pastor Osteen suggests that you start your day off by finding at least one thing to be thankful for, and don't give negative words about yourself life by speaking them.

"It's not magic, but those words go out of our mouth and they come right back into our own ears," he says. "They start to change our own self-image." So rewrite your "I am" today.

"Oprah's Lifeclass " airs on OWN .