One of the challenges we can face is how the Word of God gets used. Cults are notorious for isolating passages and bending them to say what they want them to say and they do their best to ignore other passages that could contradict their beliefs or the way they act.
But the many years of the church, has also struggled in the same way, maybe not to the extreme of cults and their teachings but we can fall into the same traps. The Word gets filtered through the character and priorities of Jesus and his life.
So yes in the old testament there are some difficult passages to contend with, but when placed by the life and teachings of Jesus, you begin to see that Jesus was indeed making all things new.