Midrash su Levitico 5:5

1) R. Yossi Haglili says: What is the intent of "and he was a witness or saw or knew, if he does not tell, then he shall bear his sin"? It applies only to testimony that can consist in seeing without knowing or in knowing without seeing, and this obtains only with a monetary claim. ("seeing without knowing": as when one says to another: "I counted out a maneh to you in the presence of so and so, who witnessed this, but I did not apprise them whether it were a gift or a loan or a pledge," and the other says: "Let them come and testify that you counted it out to me in their presence and I will pay you." ("knowing without seeing": as when one says to another: "You admitted owing me a maneh in the presence of so and so," and the other says: "Let them come and testify to this, and I will pay you." R. Akiva says (on Vayikra 5:5: "and he be guilty for one of these"): There are among these that for which he is liable (for withholding testimony) and that for which he is exempt. How so? If money is claimed, he is liable; if anything else, he is exempt.

1) (Vayikra 5:5): "Then it shall be, if he be guilty for one of these, then he shall confess where he has sinned." Whence is it derived that he is liable for each one of these ("hearing the voice, etc.") utterance of the lips, and tumah of the sanctuary and its consecrated objects) individually, and that all three are not required for liability? From "for one." Each one is implied (in all of its possible applications).

1) How so? If five say to another: Come and testify for us that so and so owes us a pledge, a deposit, a theft, and a lost object, and he says: I swear that I have no testimony for you that he owes you a pledge, a deposit, a theft, and a lost object — Whence is it derived that he is liable for each one. From: "for one," etc.