Blessing the Blesser
Question: At the recent wedding of my daughter many people kindly wished me "Mazal Tov" and blessed me that I should enjoy much nachat happiness from the young couple and all my children. What is the right thing to do in responding to such a blessing and others like it?
Answer: The blessing of any person, say our Talmudic Sages, should never be treated lightly. Since a blessing constitutes a prayer for your well-being it is proper to respond with "Amen" as we do upon hearing any blessing made in our prayers or before fulfilling a mitzvah or partaking of worldly pleasures. Even if the blessing offered appears to be for something only remotely possible, we should have this same reaction which is our way of expressing our faith that G-d can bring the blessing to fulfillment and of echoing the blessers prayer that He do so. Ramban writes that our Matriarch Sarah was rebuked by G-d for laughingly dismissing the blessing she heard about her having a child at the age of 90 from people she thought were simple Arab wayfarers instead of reacting with an affirmation of "may this be the will of G-d".
Along with the "Amen" should come an expression of gratitude to the blesser. The ideal way of saying thank you is to reciprocate with a blessing that your blesser should be blessed with the same blessing. If you are aware of a special need for your blessers in regard to finding a mate for their own child or any other area of life, this is the time to bless them that G-d should fulfill all their hearts desires.