Calvin could not and would not have any other God than Him who gives us life, who has ransomed us, and who sanctifies us—the Father, God above us; the Son, God for us; the Holy Ghost, God in us. This threefold relation with God, which Scripture revealed to him and which entirely satisfied his inward longings, forced him to recognise a _difference_ in God; but on the other hand, _unity_ being essential to the Deity, he was bound to maintain it at any cost, and he thus felt himself constrained to embrace the idea of a divine Trinity. Against this doctrine Servetus levelled his bitterest sarcasms. The Spaniard rejected what he denominated an 'imaginary Trinity;' he called those who believed in it 'tritheists,' or even atheists, and abused them in coarse language. 'Jesus is man,' he said; 'the Godhead was communicated to Him by grace, but He is not God by nature. The Father alone is God in that sense.'[180] He invited Calvin to a conference; puffed up and charmed with his own system, he fancied himself certain to convince the reformer, and flattered himself with the hope of making him his fellow-labourer. The task was not an easy one. The object of the Reformation was to raise a spiritual temple, wherein troubled souls might find a refuge; and Calvin saw rash hands presuming to make it a receptacle for every error, and, in his own energetic language, 'a den for murdering souls.' He stood forth, therefore, to maintain the apostolic doctrine, and contended that Christ, who called himself the _only_ Son of God, was a _son_, not like believers, in consequence of adoption; not like the angels, because of their communion with the Lord; but in the proper sense: and that if the son of a man has the nature of a man like his father, Jesus, the only Son of God, has in like manner the nature of God.