From the Doctrine & Covenants student manual, p. 50:
It had been just over three years since the Prophet Joseph Smith and Emma Hale had been married in the small village of South Bainbridge, New York. Joseph was now twenty-five years of age and Emma twenty-six.
The seventh of nine children born to Isaac and Elizabeth Hale, Emma was born on 10 July 1804 in Harmony, Pennsylvania. There the Prophet met and courted her while he was working for Josiah Stowell. It is reported that Emma was a beautiful woman with an attractive personality, and she had the reputation of being a refined and dignified woman who was an excellent housekeeper and cook. Her Methodist upbringing had helped her develop a great love of music.
The first three years for the newly married couple were indeed tense and trying ones. Eight months after their marriage Joseph received the golden plates from the angel Moroni. From that moment on their lives were punctuated with persecution and trial. Emma passed through these trying experiences with her husband. She was at his side during those agonizing months when Joseph lost the gift to translate. She served as his scribe for a while. Her heart must have ached when the Prophet was arrested on trumped-up charges again and again. She traveled with the Prophet on many of his missionary journeys and shared with him the joy and sorrow associated with teh preaching of the gospel. Emma was a woman of great courage and strong will. Of her the Prophet's mother, Lucy Mack Smith, wrote: "I have never seen a woman in my life, who would endure every species of fatigue and hardship, from month to month, and from year to year, with that unflinching courage, zeal, and patience, which she has ever done; for I know that which she has had to endure . . . she has breasted the storms of persecution, and buffeted the rage of men and devils, which would have borne down almost any other woman." (History of Joseph Smith, pp. 190-91).
Now, in July of 1830, possibly near her birthday, the Lord directed to Emma a revelation known as section 25 of the Doctrine and Covenants.
And from A Commentary on the Doctrine and Covenants by Stephen E. Robinson and H. Dean Garrett, p. 168-69:
Emma was baptized a member of the Church by Oliver Cowdery on 28 June 1830, and was confirmed by her husband, Joseph, in early August of that year. She was with Joseph and Oliver during the mob action and Josehp's two arrests and trials in the Colesville area. She herself was also at risk of physical injury during that time, and, like Joseph and Oliver, she suffered considerable harassment and vilification from the mobs. As a result of her New York experiences, Emma Smith was as much in need of encouragement from the Lord as were her husband and Oliver Cowdery (see D&C 24), having endured persecution with them ever since her wedding three and a half years earlier. Sometime during the month following her baptism, in July 1830, after returning home from New York to their farm in Harmony, Pennsylvania, Emma received Doctrine and Covenants 25 through her husband, Joseph.
As is the case with many who give their lives in supporting roles, we sometimes overlook how much Emma suffered and sacrificed, and what must have been the depths of her faith and commitment to the Lord. I think it is probably safe to say that Joseph couldn't have done his work without Emma by his side.