Why is a פסוק necessary to exclude - אמאי איצטריך קרא למעוטי
Summary:
The question is on the תנא; why he excludes קרקעות from a שבועה based on a כופו"כ [since he is discussing (exclusively) שבועת מוב"מ (which is הילך)].
Summary:
The order of the ד' שומרים (in the ברייתא of רב"ח) is according to their liability. The גמרא prefers to ask from all four שומרים (even though it is a ברייתא); rather than ask from some of the שומרים (even though it is a משנה).
Summary:
Whether we are גורס previously אמר ר"ח or תני ר"ח, the גמרא states here ר"ח תנא הוא ופליג to inform us that even if it is not a ברייתא, nevertheless there is no refutation of ר"ח, since ר"ח is a תנא ופליג.
They delivered it to him with witnesses - מסרי ליה בסהדי
Summary:
The owners are protected only if (besides giving it to him in the presence of witnesses) they told him (in the presence of these witnesses) that he must return it in the presence of (any two) witnesses.
If the opinion of ר"ח is valid - אי איתא לדרבי חייא
Summary:
The הלכה is like ר"ח since he is in agreement with the רבנן (and we ignore the expression of אם איתא, etc.) העדאת עדים is מחייב a שבועה even if he is a הוחזק כפרן.
Summary:
Generally the rule is that משאיל"מ; however if by implementing this rule it will cause undue losses then we say כנגדו נשבע ונוטל. Alternately, if בי"ד is preventing him from swearing, then we say כנגדו נשבע ונוטל.