The דעת תבונות or The Knowing Heart of the Ramchal is an excellent book on Jewish philosophy. In it, he explores some basic questions regarding our faith in G-d.
He emphasizes the importance of remembering Hashem’s inherent goodness. One who is good, has a need to share his good with others. The Ramchal writes that it would not have been difficult for Hashem to create perfect human beings. But because of His goodness, we were created imperfect with the potential of acquiring perfection.
For the same reason, G-d Himself created good and evil. By giving us challenges to make the right choices, and the spiritual work, we are charged to do, there is the greatest potential of reward. In this way, He is able to share His goodness on a much higher level.
Interesting thoughts from the Ramchal in דעת ותבונות.