Use of gender-specific and gender-neutral words together

These are sample sentences we usually come across:

1. This is a husband‘s provision for his spouse.
2. This is a wife‘s provision for her spouse.

One may find a similar sentence reading “A husband’s (or wife’s) provision for a spouse after separation or divorce” at http://www.oxforddictionaries.com/definition/english/alimony

“Husband” and “wife” are gender-specific words, while “spouse” is a gender-neutral word. Logic says that when a gender-specific word “husband” or “wife” is used in a sentence, the opposite of that word in the sentence should also be gender-specific (and should not be a gender-neutral word). If so, then how could one use gender-specific and gender-neutral words together in the sentences like the ones cited above? Or, how could there be a sentence like the one cited at the link provided above?

To me, the correct sentences would be:

1. This is a husband’s provision for his wife.
2. This is a wife’s provision for her husband.

Or, one could perhaps also say:

1. This is a spouse’s provision for the other spouse.
2. This is a spouse’s provision for the other.

I admit that I may be wrong. Can someone shed some light?