strengthening and establishing the hearts of the disciples; encouraging them to remain firm in the faith, saying, “It is through many tribulations and hardships that we must enter the kingdom of God.”
Many christians when faced with one challenge or the other tend to deviate in their believe as well as compromise their stands. Some even go to the extent of accusing God.
For the fact that you are born-again does not mean that trials and temptations won't come, they'll surely come, even more than before. so, when these things happen, don't panic and grief for they come to build you and your faith.
Your joy should be that the suffering and tribulations you face now can't be compared to th latter glory.
kudos @reliquary