In the early history of the restoration of the gospel - Brigham Young and Heber C. Kimball were called by the Lords Prophet to serve a mission in England. They were sick and destitute, and their families were also. As they left their families to obey the Lords command - they stood in the wagon and took off their hats and waved to their loved ones - shouting ®Hurray for Israel®. This bolstered everyone's courage to do the Lords will first, and made them feel better about their situation.
In the Movie - ®The other side of Heaven® John Grober and Fakir Pouha used this example to give them courage to do the Lords will also. they did not want to part - they loved working together- but the Lord called Feki to labor elsewhere in the mission. Raising their arms above their heads as a symbol of the obedience and sacrifices of the churches early missionaries, they also shouted ®Hurray for Israel® the Lords will be done.