We are studying Maseches Kesubos, chapter 8, mishnah 8. This mishnah deals with the lien on a husband's property for payment of the kesubah - both in the case of a yavam and in the case of an ordinary husband.
"Lo yomar lah: harei kesubaseich munachas al hashulchan":
These words are directed at the yavam: he may not tell his yevamah that her kesubah is set aside and lying ready for her on the table. That is, he has no right to designate a particular sum of money, or something worth money, and earmark it for her kesubah, "ela kol nechasav achra'in lakesubah" - rather, all of his property, including the assets he received from his deceased brother, is responsible for the payment of her kesubah, and he may not sell any of it.
"Vechen lo yomar adam le'ishto":
The same law applies to an ordinary man with regard to his wife, and not only to a yavam with regard to his yevamah: he may not tell her "harei kesubaseich munachas al hashulchan" - for setting aside a particular sum of money on the side is liable to undermine her sense of security. The money is already lying there and serves him no purpose, and he is free to divorce her at any moment. Therefore, "ela kol nechasav achra'in lekesubasah" - all of his property is responsible for the payment of her kesubah.
The lien on the property and its sale:
In the case of an ordinary husband and wife, the husband may sell his property; although it is under lien to the kesubah, this is not a lien that prevents him from selling. However, if he sold it, and afterward they were divorced and he has no other means of paying, or he died and his estate contains no other funds, she turns to the buyers who purchased those properties and collects from them, because her lien preceded their purchase.
"Gershah - ein lah ela kesubasah":
Here the mishnah returns to the law of the yevamah: if the yavam divorced his yevamah, she takes only her kesubah, while the rest of her late husband's property is not hers but remains in the hands of the brother.
"Hechezirah - harei hi kechol hanashim":
If the yavam took back the yevamah whom he had divorced and married her anew - as he is permitted to do - and she had not yet collected her kesubah, she is like all other women: a woman whose husband divorced her and took her back before he paid her kesubah is remarried on the basis of the original kesubah. Therefore, "ve'ein lah ela kesubasah" - that same original kesubah that was written for her, which in the case of the yevamah originates in the funds of her late husband that came into the hands of the yavam.
In summary: In this mishnah we learned that a husband - and likewise a yavam - may not set aside a particular sum and say "your kesubah is lying on the table"; rather, all of his property is responsible for the kesubah. With an ordinary husband the lien does not prevent a sale, but the wife collects from the buyers because her lien came first. If the yavam divorced his yevamah, she receives only her kesubah, and the rest of the deceased's property remains in his hands. And if he took her back before she collected, she is like all other women, and she receives only her original kesubah.