done again - “a second time”: an aggravation of your offense (Neh 13:23-31), in that it is a relapse into the sin already checked once under Ezra (Ezr 9:10) [Henderson]. Or, “the second time” means this: Your first sin was your blemished offerings to the Lord: now “again” is added your sin towards your wives [Calvin].
covering ... altar ... with tears - shed by your unoffending wives, repudiated by you that ye might take foreign wives. Calvin makes the “tears” to be those of all the people on perceiving their sacrifices to be sternly rejected by God.