Entrust is a skill that transfers (usually) MP from the caster to the target. It is non-magical, meaning it will still work if the caster is under Silence, making it a great strategic option in such cases. There exists a similar spell for HP, which is called Martyrdom (and Martyrdom II), and also a spell which transfers a skill command from the caster to the target, called Skill Entrust. It has a more powerful version, Skill Entrust II, which transfers the skill command to the target, but the skill will use the MP of the caster, not the target. Entrust is usually free, while Entrust II has a small MP cost.