John Calvin on John 17:18

18. As thou hast sent me into the world. He confirms his prayer by another argument; namely, because the calling of Christ and of the apostles is the same calling, and is common to both. “I now,” he says, “appoint them to an office, which I have hitherto held by thy command; and, therefore, it is necessary that they should be furnished with the power of thy Spirit, that they may be able to sustain so weighty a charge.”