One of those reminders, and the central theme of the book, is to remember that God IS the gift of the Gospel.
What is meant by this, is the Gospel purely exists in order to exemplify God's glory to us.
Some people, even Christians, can misinterpret the message of the Gospel. They choose to focus on the promises provided in it. Rather than God, their faith is rooted in happiness from the miracles, or how they will be positivity perceived by others for their faith, or dreading the possibility of Hell.
Remember that anything less than God pertains to good, positive things as well: employment, food, family, children, etc. If ANYTHING takes precedence over God, or if our joy is rooted in anything other than God, we are on the wrong path.
For most of us, we are too egotistical to bother making God the foundation of our lives. This is because we "... have been saturated for decades with doctrines of self-esteem. We have absorbed a definition of love that makes US the center." We make ourselves the center of the universe; "main character energy," so to speak.
We acknowledge ourselves for our achievements, our status in life, our families, etc. and believe that we and we alone deserve the credit -- nobody else played a part in it, and if they did, we only give credit to earthly and humanly means.
There is the "if you scratch my back, I'll scratch yours" believer -- they mould God into a delusion who only encourages their wants. Only if they benefit from the relationship will they serve God.
Or, the "saint on Sunday, sinner by Monday" approach: the Gospel's message is heard, but they still refuse to make God the focus of their lives.
However, what people forget -- again, while only focusing on the good things promised in the Bible -- is they are conveniently choosing to neglect the other things promised as well: "... terrible things like tribulation, distress, persecution, famine, nakedness, danger, sword, and death."
And, funnily enough, they are all gifts to us as well, for these are "... to make us rely not on ourselves but on God who raises the dead." Our suffering is the ultimate reminder of what awaits us after and draws us closer to God.
For some, these gifts -- suffering -- is incomprehensible. "What this shows is how far above the glory of God most people value pain-free lives. For most people, love is whatever puts human value and well-being at the highest point."