A good example comes from Boxer, who follows the Revolution entirely on trust. He works harder than any other animal, and his strength is vital to the farm's success and to their battles against humans.
Boxer, who had now had time to think things over, voiced the general feeling by saying: "If Comrade Napoleon says it, it must be right."
His trust is so blind that he submits to Napoleon's every whim, accepting this abuse as part of his payment for living in the new, "free" society. However, his trust is betrayed as Napoleon sells him to a glue-maker instead of allowing him to retire, as the initial plan always stated.
The time had been when a few kicks from Boxer's hoofs would have smashed the van to matchwood. But alas! his strength had left him...
(Orwell, Animal Farm, msxnet.org)
The betrayal of Boxer is one of the final nails in the coffin of the original Revolutionary ideals. Instead of being allowed to retire and reap the reward for his hard work, Boxer is sold for enough money to buy the pigs a case of whiskey; Boxer was used, abused, and discarded when he was no longer useful. In this way, trust is shown almost as a vice; it is better to trust and verify than to trust blindly.
One may be that Boxer is so open to trust that Napoleon is right that he goes round chanting it all the time. It shows how easy it was to convinse the simple animals.
Also that all the animals trust that all the bad things happened because of snowball.
How clover trusts the Donkey
How all the animals trust snow balls speachs.