According to this post, there are two dangers in preaching the Old Testament in light of Jesus. The first is to force Jesus into every passage, and the second is to not connect Old Testament passages to Jesus at all. The author argues of a more organic middle ground that is faithful to the Old Testament and the cross to which it points.
The preaching of the word is the hight of the worship service; therefore, it is the most vital place for the proclamation of the Gospel of King Jesus. So, this author argues when your sermon omits Jesus you are doing a disservice to the Bible and your hearers.
If anyone had a right to ask others to pray for his comfort and ease of difficulties it was the Apostle Paul, yet that is not what he asks of those to whom he requests prayer. Rather, he asks for boldness even in the face of difficulties, and so should we.