Mark 13:28

Now learn a parable of the fig tree; When her branch is yet tender, and putteth forth leaves, ye know that summer is near:

The tender branch of the fig tree putting forth leaves is a lesson in recognizing nearness, for by it summer is known to be near. In the same way, seeing the things Jesus foretold come to pass shows that the predicted events are approaching. The nearness thus indicated is that His coming is nigh, even at the doors.

The saying belongs to Jesus' answer about the destruction of the temple and the signs by which the disciples would know that the predicted events were near. That discourse describes two crises together, the destruction of Jerusalem and Christ's coming and the end of the world, so the prophecy extends beyond the fall of Jerusalem to the final judgment. In its wider setting it stands with the warning that cities filled with extreme sin will face destruction by earthquake, fire, and flood, and that human wealth, grand buildings, and efforts to secure them cannot withstand God's authority.