Rava Comforts Rav Ilish
Rava disproves Rav Ilish's ruling and Rav Ilish is embarrassed, so Rava comforts him: Hashem made sure Rava was there the one time Rav Ilish would have erred.
Rav Ilish offered his opinion on a halachic question. Rava, however, disagreed and conclusively disproved Rav Ilish’s answer. Rav Ilish was embarrassed. He figured that Rava would now assume that Rav Ilish could not be relied upon for correct rulings. The one time that Rav Ilish issued a ruling in front of Rava, it was the incorrect one!
Rava, sensing Rav Ilish’s embarrassment, appeased him by quoting the pasuk: “I, Hashem, will hasten it in its time” (Yeshaya 60:22). The Rashbam explains that Rava’s take on the incident was the exact opposite of what Rav Ilish was thinking. Of course, Rav Ilish always issued correct rulings. The one time he was about to err, Hashem ensured that Rava was around to correct him. This is how Hashem deals with tzaddikim, ensuring that when they require assistance, that assistance is nearby.