After Jesus told the disciples that he would leave the world and go to the Father, the disciples understood Jesus. The disciples pointed out on how Jesus is now "speaking plainly" and "using no figure of speech" (16:29). Jesus's plain speak helps further the disciples belief in Jesus. In particular, the disciples know that Jesus "know[s] all things", "[has] no need that anyone should question", and "came forth from God" (16:30). The "all things" that Jesus knows from context likely refers to Jesus's future plans as well as the immediate scenario, but it's heavily implied that Jesus knows much more.
In particular, Jesus knows that in the coming hour, the disciples "will be scattered, each to his own, and will leave [Jesus] alone" (16:32). Jesus likely knew the scattering from the pressure that the disciples would face (and how the disciples would encounter fear, emotions, and force). It's also worth noting that after the ascension, the disciples travelled to different locations. However, even with the pressure, Jesus reassures the disciples that "the Father is with [Jesus]" (16:32). In other words, the Father is on board with what Jesus would do (and vice versa).