Genesis 45:26 - Coke's Commentary on the Holy Bible

Jacob's heart fainted— The Vulgate, and some others, render this passage, Jacob awoke, as it were, out of a dead sleep, yet he believed them not. The particle כי ki, rendered for in our version of the Bible, often signifies but, but yet, or although: and thus the meaning of the passage is, that though Jacob did not perfectly believe, or had not heard enough to be sufficiently confirmed in the belief of their words; yet the very hearing of Joseph's being yet alive, whom he thought so long dead, gave such a sudden shock to his blood and animal spirits, and poured in such a tide of joy upon his heart, as quite overpowered the venerable patriarch, and made him fall into a swoon. That sudden transports of joy, as well as other passions, will produce this effect, is well known from experience. Le Clerc quotes a remarkable instance out of Aulus Gellius. "After the battle of Cannae, in which the Roman army was cut to pieces, an ancient mother, hearing that her son was slain, pined with grief and melancholy; but the report proved false, and the youth returned not long after to Rome. The mother, struck with the sudden sight of him, was so overpowered with the fulness of unexpected joy which rushed in upon her, that she swooned away and died."