Will not discuss the story but Guide has several messages like faith, salvation, aspiration etc but above all it conveys the message of transformation that one goes throughout his life.
Dev Anand (Raju) as a Guide, involves in forging, goes to jail, supports a woman, falls in love, inspires her, becomes a sage etc. All this shows that there is a good and evil within us and it depends on us as to which side we want to grow.
The movie inspires us that our quest to be a better person should go on. Raju becomes a sage when he realises that he has cheated Rosy. The villagers start blindly believing in him and have many expectations from him.
Instead of getting corrupt he feels a sense of responsibility within him and the faith of the villagers awakens him as a great person. He is worshipped as God by the villagers.
Unable to break their faith he sacrifices his life. Finally it rains in the drought hit village. The villagers rejoice in the rain which is also a reflection of Raju's tears that their faith has won.
Somewhere it also tries to say that the problems of others can also help you to lift yourself as a person and their cause can provide you the ultimate awakening.
Personal opinion, might differ.
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