Jesus Christ is citing Numbers 21, where God punishes Israel with fiery serpents for their sin. And Jehovah will save Israel through a graven serpent lifted up. By citing Numbers 21 and using this language, Jesus is teaching us that Numbers 21 is a figure of sin and salvation. And the graven serpent itself is a type of his person and work.
The situation, intending communicants, in which you are now placed is one of peculiar interest and solemnity. In obedience to the commandment of the King of Zion, you are professedly met to commemorate the decease, which, in the days of his flesh, he accomplished at Jerusalem.
Dear friends, our communicating work at this time is over; our preaching and your hearing work is almost over; but our account for these things is still before us—who knows how near! Let us think what we have done, and what we have got, that will abide the trial. In this solemn charge of Heaven, now read and directed to your conscience and mine, we have: 1) An awful warning of the future judgment, from the lips of the Judge: Behold, I come quickly. 2) A solemn charge to take heed to ourselves in the view of our certain and sudden appearance before God, the Judge of all. Hold that fast which thou hast, that no man take thy crown.
From the outset, the sixteenth-century Scottish Reformed Church was firm in its pursuit of tutoring and examining communicants, and this preparation intensified in the weeks leading up to the administration of the Lord’s Supper. The First Book of Discipline (1560) enjoined, “All ministers must be admonished to be more careful to instruct the ignorant than ready to serve their appetite and to use more sharp examination than indulgence in admitting to that great Mystery such as be ignorant of the use and virtue of the same. And therefore we think that the administration of the Table ought never to be without examination passing before and specially of them whose knowledge is suspect.”
