2 But of His own passion itself, which lay not in any necessity He was under, but in His own power, all that He said in His discourse to the Jews was, “I go away.” For to Christ the Lord's death was His proceeding to the place whence He had come, and from which He had never departed. “I go away,” said He, “and you shall seek me,” not from any longing for me, but in hatred. For after His removal from human sight, He was sought for both by those who hated Him and those who loved Him; by the former in a spirit of persecution, by the latter with the desire of having Him.
In the Psalms the Lord Himself says by the prophet, “A place of refuge has failed me, and there is none that seeks after my life;” and again He says in another place in the Psalms, “Let them be confounded and ashamed who seek after my life.” He blamed the former for not seeking, He condemned the latter because they did. For it is wrong not to seek the life of Christ, that is, in the way the disciples sought it; and it is wrong to seek the life of Christ, that is, in the way the Jews sought it: for the former sought to possess it, these latter to destroy it.
Accordingly, because these men sought it thus in a wrong way, with a perverted heart, what next did He add? “You shall seek me, and”— not to let you suppose that you will seek me for good— “ye shall die in your sin.” This comes of seeking Christ wrongly, to die in one's sin; this of hating Him, through whom alone salvation could be found. For, while men whose hope is in God ought not to render evil even for evil, these men were rendering evil for good. The Lord therefore announced to them beforehand, and in His foreknowledge uttered the sentence, that they should die in their sin.
And then He adds, “Whither I go, you cannot come.” He said the same to the disciples also in another place; and yet He said not to them, “You shall die in your sin.” But what did He say? The same as to these men: “Whither I go, you cannot come.” He did not take away hope, but foretold delay. For at the time when the Lord spoke this to the disciples, they were not able to come whither He was going, yet were they to come afterwards; but these men never, to whom in His foreknowledge He said, “You shall die in your sin.”
Source: Tractates on the Gospel of John (New Advent)