Is it ontologically and ethically 'safer' to believe in free will rather than determinism? Samuel Fancourt thought so. Here is a passage from one of his many books on free will theology.
Were we to err in this matter, it were infinitely more safe (even in our fallen State) to err on the side of Liberty than against it. … If we are not free, but wholly passive, it can do us no hurt to think ourselves free. What I am under a Necessity to do and be, I shall do and be notwithstanding. But if we are really free, and think we have no Freedom, it may do us much Hurt, it may turn to our infinite Hurt, as it may tempt us to neglect that Part upon which Life and Immortality depend. Ay, it may not only prove an Injury to our selves, but to the World about us, whilst those valuable Talents, which were given for the publick Good, are either wickedly imploy’d against it, or slothfully buried, for want of a Vigorous and timely Resistance against the Flesh, the World, and the Devil.
Source: Samuel Fancourt. An Appendix to a Letter to the Reverend Mr. Norman, in Two Parts. Now available on Kindle.