This is the same verse that the enemy used on Jesus during His temptation in the wilderness. But, as usual, the enemy took his references out of context. Note that the situation is presented twice, with more intensity. Normal lions and serpents, we will tread on. The really big guys, we will trample .
Lions represent open adversaries, serpents hidden adversaries.
Both are kept from us. For love given to the Lord, we are given protection in return. For service, we are given the protection of the Master himself. He will deliver us. Many people are all too ready to ascribe the status of Creator of the World to God, but for some reason they deny that He can help them in times of trouble.