There had been some contention and disputes, “many little dissensions and disturbances among the people.” The text says, “It became expedient that the word of God should be declared among them.” Alma was gone. Helaman and the family probably mourned over his loss, although they did not know for certain that he was dead, and there was no body to bury.
There would likely have been an interlude, a time when they continued to think that Alma might yet return, and then a time when Helaman finally said to Shiblon and Corianton that they knew well what their father would have wanted them to do. They knew they needed to hold the place together, so they went forward, they “regulated” the church, and put new priests and teachers in place. That was what Alma had done. When he went to the city of Gideon, he appointed priests and teachers as needed. So Helaman and his brothers went and did the things that Alma himself had done.