Sirach 35:20

20 Mercy is seasonable in the time of affliction, as clouds of rain in the time of drought.

Sirach 35:20 In-Context

18 For the Lord will not be slack, neither will the Mighty be patient toward them, till he have smitten in sunder the loins of the unmerciful, and repayed vengeance to the heathen; till he have taken away the multitude of the proud, and broken the sceptre of the unrighteous;
19 Till he have rendered to every man according to his deeds, and to the works of men according to their devices; till he have judged the cause of his people, and made them to rejoice in his mercy.
20 Mercy is seasonable in the time of affliction, as clouds of rain in the time of drought.

The Brenton translation of the Septuagint is in the public domain.