John Calvin Commentary John 18:9

"that the word might be fulfilled which he spake, Of those whom thou hast given me I lost not one." — John 18:9 (ASV)

I have lost none. This passage appears to be inappropriately quoted, as it relates to their souls rather than to their bodies. For Christ did not keep the apostles safe until the very end; but this He accomplished: that amidst incessant dangers, and even in the midst of death, still their eternal salvation was secured.

I reply, the Evangelist does not speak merely of their bodily life, but rather means that Christ, sparing them for a time, made provision for their eternal salvation. Let us consider how great their weakness was; what do we think they would have done if they had been brought to the test?

Therefore, since Christ did not choose for them to be tested beyond the strength He had given them, He rescued them from eternal destruction. And from this we may draw a general doctrine: that though He tests our faith by many temptations, He will still never allow us to come into extreme danger without also supplying us with the strength to overcome.

And indeed, we see how He continually bears with our weakness: He puts Himself forward to repel so many attacks of Satan and wicked men, because He sees that we are not yet able or prepared for them. In short, He never brings His people into the field of battle until they have been fully trained, so that even in perishing they do not perish, because there is gain provided for them both in death and in life.