Matthew Henry on Exodus 38:1-8

In all ages of the church there have been some persons more devoted to God, more constant in their attendance upon his ordinances, and more willing to part even with lawful things, for his sake, than others. Some women, devoted to God and zealous for the tabernacle worship, expressed zeal by parting with their mirrors, which were polished plates of brass. Before the invention of looking-glasses, these served the same purposes. (Ex 38:9-20)