The withered fig tree
Whether the fig tree withered at once, as Matthew tells it, or on the following day, as Mark.
Matthew 21:18-22
18Now in the morning, as he returned to the city, he was hungry.
19Seeing a fig tree by the road, he came to it, and found nothing on it but leaves. He said to it, “Let there be no fruit from you forever!” Immediately the fig tree withered away.
20When the disciples saw it, they marveled, saying, “How did the fig tree immediately wither away?”
21Jesus answered them, “Most certainly I tell you, if you have faith, and don’t doubt, you will not only do what was done to the fig tree, but even if you told this mountain, ‘Be taken up and cast into the sea,’ it would be done.
22All things, whatever you ask in prayer, believing, you will receive.”
Mark 11:12-21
12The next day, when they had come out from Bethany, he was hungry.
13Seeing a fig tree afar off having leaves, he came to see if perhaps he might find anything on it. When he came to it, he found nothing but leaves, for it was not the season for figs.
14Jesus told it, “May no one ever eat fruit from you again!” and his disciples heard it.
15They came to Jerusalem, and Jesus entered into the temple, and began to throw out those who sold and those who bought in the temple, and overthrew the money changers’ tables, and the seats of those who sold the doves.
16He would not allow anyone to carry a container through the temple.
17He taught, saying to them, “Isn’t it written, ‘My house will be called a house of prayer for all the nations?’ But you have made it a den of robbers!”
18The chief priests and the scribes heard it, and sought how they might destroy him. For they feared him, because all the multitude was astonished at his teaching.
19When evening came, he went out of the city.
20As they passed by in the morning, they saw the fig tree withered away from the roots.
21Peter, remembering, said to him, “Rabbi, look! The fig tree which you cursed has withered away.”
What each tradition says
Rabbinic / Midrashic
No sourced position found. Checked the Jewish Encyclopedia (1905), articles "Jesus of Nazareth" and "New Testament" — the fig tree appears only as a Midrash symbol (Cant. R. ii. 13), never on the timing of the withering; Sefaria holds no Gospel text or commentary. No rabbinic position on this dispute found.
Patristic
Augustine says the tree did not wither at the exact time they saw it, but at the moment it was cursed. They saw it not in the process of drying up but already completely dried. So they learned it had withered immediately at the Lord's sentence.
Augustine, Harmony of the Gospels (Nicene and Post-Nicene Fathers, First Series, Vol. 6; S.D.F. Salmond trans.) — Book II, ch. 68 (§131)
Catholic
According to Haydock, the disciples' surprise at the sudden withering of the fig tree occurred the following morning. He refers to Mark 11:20.
George Leo Haydock, George Haydock's Catholic Bible Commentary (1859) — On Matthew 21:20
Orthodox
No sourced position found. Checked archive.org for a public-domain English Theophylact of Ohrid or Euthymius Zigabenus Gospel commentary (none — only a 1636 Greek edition of Theophylact on Paul); Philaret’s Longer Catechism (dogmatic, no passage commentary); Acts and Decrees of the Synod of Jerusalem (1899 trans.); pravoslavieto.com (no English commentary on Matthew 21). No Eastern treatment of the fig-tree timing found.
Reformed / Protestant
Calvin finds an easy solution: Matthew and Mark agree that Christ cursed the tree the day after his solemn entrance into the city. Mark states what Matthew omitted—that the disciples observed it the following day—so Mark’s clearer order of time makes no contradiction.
John Calvin, Commentary on a Harmony of the Evangelists, Matthew, Mark, and Luke, Vol. 3 (Calvin Translation Society, 1846) — On Matthew 21:18-22 / Mark 11:12-14
Evangelical
Jamieson, Fausset, and Brown say the full blight probably did not appear at once, and in the dusk perhaps they had not observed it. Mark distinguishes the days; Matthew, intent on the truths taught, presents the whole as happening at once, like Jairus’s daughter’s two stages. The difference is only summary versus detailed narrative, each confirming the other.
Robert Jamieson, A. R. Fausset, David Brown, Commentary Critical and Explanatory on the Whole Bible — On Mark 11:20