There is a well-known story, true or not I do not know, of a son who wanted money from his father before parting ways. The father would not give the money and the son left. Later it turned out that the father had put an envelope of money in the son's siddur or tefillin bag, which had gone undiscovered until it was too late, because the son never used his siddur or tefillin. Or something like that.

This story has come to life, sort of..

According to a story on Kikar, a secular fellow from Ramat Aviv was seated near a Chabad family from Crown Heights on an airline flight. After becoming friendly on the flight, the Chabadnik suggested he start putting on tefillin and tallis, to which the secular fellow agreed.

Michael, the guy from Ramat Aviv, goes to his local Chabad House with tallis and tefillin in tow, and even bringing along his late father's tallis as well. Michael decided he preferred to use his late father's tallis, and the Rabbi was going to show him how to wrap the tallis and wear it.

When they took out the tallis, they found an envelope placed in its folds 2 checks form 1995, each to the sum of 62,000nis.

While it is not quite as dramatic as the known story, as the father did not hide it there for his son in this case, it does turn out that someone had owed the father money and had paid it back with these two checks. The father simply, probably, put them away there until he could deposit them but died before getting a chance to go to the bank (based on the dates of the checks and the fact that the father had died form a heart attack while driving - so goes the story). The son, Michael, recognized, that had he put on his tefillin after the father died, he would have found the money back then.

Supposedly Michael committed to putting on tefillin regularly.