Перевод на английский пословицы"Первое слово дороже второго"

тут есть поисковик по пословицам ( к сожалею вашу не нашла, но может пригодится) :
http://alexander.ssdn.ru/search/

хотя может так:
A word spoken is past recalling. =Слово не воробей, выпустишь - не поймаешь.

Аналога этой идиоме я не нашла. Тут нужен описательный перевод.

я бы перевел это так:
only the first made call counts.

good (MORAL RIGHT) /gUd/ adjective better, best
morally right or based on religious principles; kind and helpful:
She led a good life.
Try to set a good example to the children.

Good heavens/grief/gracious! (ALSO Good God/Lord!)
used to emphasize how surprised, angry, shocked, etc. you are

be as good as your word
to do everything that you promise someone you will:
He said he'd call every day and he was as good as his word.

in good faith
If something is done in good faith, it is done sincerely and honestly:
She was acting in good faith for her client.

good /gUd/ noun
that which is morally right:
There is an eternal struggle between good (= the force which produces morally right action) and evil.
Ambition can sometimes be a force for good.

no good INFORMAL OLD-FASHIONED
morally bad:
I'd keep away from him if I were you - he's no good.

be up to no good INFORMAL
to be behaving in a dishonest or bad way:
He certainly looked as if he was up to no good.

the good plural noun
all the people who are good:
You can't buy your way into the ranks of the good.

First word dearer second