every karma one create is like a stone thrown into the water and
will sink to the bottom.
The idea of being 'saved' is generally considered new in
Buddhism. But King Milinda (Menandros, a Greek ruler in Sagara,
about 115 BC) questioned a learned priest Nagasena, saying that it
was unreasonable that a man of bad conduct could be saved if he
believed in a Buddha on the eve of his death. Nagasena replied: "A
stone, however small, will sink into the water, but even a stone
weighing hundreds of tons if put on a ship will float."
http://www.taichido.com/chi/newbud/pure1.htm
The Questions of King Milinda Sutra contains the following
parable:
We can see from this passage that thanks to "other-power," the
Pure Land method can benefit the practitioner, however heavy his
karma may be. The huge block of stone represents the weight of
heavy karma, the boat symbolizes the power of Amitabha Buddha's
Vows. Therefore, the cultivator should not think that residual
greed, anger and delusion will prevent him from achieving rebirth
in the Pure Land. This example should also resolve doubts
concerning past heavy karma, as in doubt number one above.
A minute grain of sand, dropped on the surface of the water,
will sink immediately. On the other hand, a block of stone, however
large and heavy, can easily be moved from place to place by boat.
The same is true of the Pure Land practitioner. However light his
karma may be, if he is not rescued by Amitabha Buddha, he must
revolve in the cycle of Birth and Death. With the help of Amitabha
Buddha, his karma, however heavy, will not prevent his rebirth in
the Pure Land.
http://www.ymba.org/BWF/bwf101.htm
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