Commandments given regarding spirituality are important. Really, all commandments are spiritual in one sense or another, but some are specifically spiritual. Following these commandments, or Mormon rules, brings happiness to those who faithfully obey.
God’s purpose in creating us was to “bring to pass the immortality and eternal life of man” (Moses 1:39). The scriptures tell us that the only way to live with God again is by following His commandments. Jesus Christ, the literal Son of God and Savior of the world, atoned for the sins of the world. He also overcame the bonds of death when He rose from the dead. He has made it possible for us to be forgiven of our sins and shortcomings. It is only through the power of the grace of the atonement that we can hope to return to God.
Living with God requires that we be able to live the way God does: perfectly. Since we are all imperfect beings, this is impossible for us here and now. The commandments are God’s law. If we are not able to live by them, we cannot live with Him again. This life is a time to prepare to live with God again by learning to live His law (Alma 34:32). We can and will make mistakes, but we must then repent through the power of the atonement. Eventually, if we are faithful and endure, we will learn to keep this law perfectly and will be cleansed through the atonement, finally able to live with God again.