Proverbs 25:13

As the cold of snow in the time of harvest, so is a faithful messenger to them that send him: for he refresheth the soul of his masters.

Ordinarily, snow would be a disaster in the time of harvest, but here it means snow added to a drink of water and given to a reaper in the harvest field will be refreshing to them. Just as an iced drink refreshes on a hot day, so a faithful messenger refreshes those who sent them.