But these were vague, half-realized thoughts. The word 'labour,' or 'work,' was familiar to them. Jesus meant, they thought, that God would not give them anything which they did not earn. '_What shall we do_,' said one, who was the spokesman of the rest, '_that we may work the works of God_?' As often happens, the language was accurate beyond the conscious intention of the person who used it. He desired to know what work they should work _for_ God, whereas it was really a work _of_ God that was demanded. '_Jesus answered, This is the work of God, that ye believe on Him whom He hath sent._' God was working upon them; He was calling them to trust their King and their Friend; to give up their hearts to the Lord of their hearts--to Him who could alone quicken them to any good and fruitful work. Of course, they understood by the expression, '_Him whom He hath sent_,' that Jesus was claiming to be Messiah,--the sent from Heaven. '_They said therefore unto Him, What sign shewest Thou then, that we may see, and believe Thee? What dost Thou work? Our fathers did eat manna in the desert; as it is written, He gave them bread from heaven to eat._' Jesus had fed them in the desert when they were fainting. That was a strange and great act, no doubt, worthy of a Prophet, perhaps of a King. But the manna had actually dropped from heaven out of the clouds. If He came from Heaven, would He have merely taken the bread in His hands and blessed it? Would there not have been a sign like that which showed Moses to be indeed the messenger of God? Would there be no appearance in the sky? It was the question of people whose minds were perplexed about Heaven, and who, happily, had not found out seemly phrases in which to veil their perplexity. A material heaven--a heaven of sky and clouds--was what they saw and confessed. They had a dim vision of something beyond this. Their hearts yearned for a Heaven as calm as that upon which their eyes gazed; as full of light, as productive of life, but yet altogether different from that. What it was, where it was, they could not tell. Do you think we should have helped them if we had talked to them about an intellectual Heaven or a subjective Heaven? Do you think such nonsense can be of much help to ourselves?