Paulus, Trusts, Book I. Even if I should charge my heir with a trust as follows, “I ask you, Lucius Titius, to charge your heir to pay ten aurei to Mævius,” the trust will be valid; provided that, after the death of Titius, its execution can be demanded from his heir. This opinion was also held by Julianus. 1A trust cannot, however, be created as follows, “If Stichus should become the property of Seius, and should enter upon my estate by his order, I ask Seius to pay such-and-such a sum,” since anyone who obtains an estate through chance, and not by the will of the testator, or acquires a legacy under such circumstances, ought not to be burdened with the obligation of a trust; and the principle should not be adopted that you can bind anyone by a request of this kind when you give him nothing.

Paulus, Trusts, Book I. If a legatee, who has been charged with a trust, claims the legacy, he can only be compelled to pay to the beneficiary of the trust as much as will be required by the judge; or, if the judge does not compel him to pay anything, he must assign him his right of action; for it is unjust that he should sustain the risk attending a lawsuit, if the case should be lost through no fault of the legatee. 1A slave of the heir cannot be charged with a trust, unless the latter is requested to manumit the slave. 2Where a testator provided that any of his estate which might come into his father’s hands should be given to his daughter, so that, in this way, she would have more than she would otherwise obtain from her father’s estate, the Divine Pius stated in a Rescript that it was evident that the testator intended that the delivery of the property should be made after the death of the father.

Paulus, Trusts, Book I. If anyone grants freedom to a slave by will, both directly and under a trust, it is in the power of the slave to choose whether he will obtain his freedom directly, or by virtue of the trust. This the Emperor Marcus also stated in a Rescript.