Spendthrift clauses can be confusing to trustees. The general idea with a Florida Spendthrift clause is that the beneficiaries cannot assign their interest in the trust to a creditor ( voluntarily or involuntarily)
Here is the test found in a typical clause under the new Florida Trust Code
Spendthrift Provisions. Each trust created by this Trust Agreement shall be a spendthrift trust to the fullest extent allowed by law. Prior to the actual receipt of trust property by any beneficiary, no property (income or principal) distributable under any trust created by this Trust Agreement shall, voluntarily or involuntarily, be subject to anticipation or assignment by any beneficiary, or to attachment by or to the interference or control of any creditor or assignee of any beneficiary, or be taken or reached by any legal or equitable process in satisfaction of any debt or liability of any beneficiary, and any attempted transfer or encumbrance of any interest in such property by any beneficiary hereunder prior to distribution shall be void.
The most common application of a Spendthrift Provision is to protect against involuntary assignment or bankruptcy.