A Bedouin came to the Messenger Muhammad to test him. He had a date in his hand and asked what do you think is the destiny of this date? The Messenger replied, whatever you decide to do with it (eat it or not). Another story goes like this: A Bedouin came to visit the Messenger. The Messenger asked him the visitor's camel. The Bedouin replied that he left it outside "trusting God". The Messenger asked to Bedouin to go tie the camel and then trust God!!
Destiny is like travellers in a train. They have a lot of freedom to do what they want but ulitmately they will arrive at their destination and embark!!