The Church has announced that the Mutual theme for 2018 is Doctrine and Covenants 19:23:

“Learn of me, and listen to my words; walk in the meekness of my Spirit, and you shall have peace in me.”

The emphasis is on Peace in Christ.

The purpose of the yearly theme is to provide opportunities for youth worldwide to learn about,
study, internalize, and apply the principles taught in the scripture. Youth are encouraged to
memorize the scripture, study its doctrine, and act on the principles learned throughout the year.

The theme may also be used to enrich Mutual opening exercises, as a topic for sacrament meeting talks by youth, or to provide focus for youth activities, including camps, youth conferences, and devotionals. Leaders are encouraged to emphasize any of the principles taught in this verse to help meet the needs of the youth they serve.

Resources for introducing the theme, including videos and music, will be available online at youth.lds.org by the end of 2017 in Chinese, English, French, German, Italian, Japanese, Korean, Portuguese, Russian, and Spanish. An email will be sent to leaders when these resources are available. Additional materials supporting the theme will be made available in Church magazines and on LDS.org throughout 2018.

See a list of scriptures used as Mutual themes over the past few years.