Moreover, as there are engagements on Christ’s part, relating hereunto, and in pursuance thereof, they are said to be in his hand; so the Father has given them an additional security, that they shall be preserved from apostasy; and therefore they are also said to be _in his hand_; from whence _none can pluck them out_; and from thence it is argued, that _they shall never perish_, John x. 28, 29. And we may observe, that the life which Christ is said to give them respects not only the beginning thereof, in the first grace which they are made partakers of in conversion; but it is called _eternal life_, which certainly denotes the completing of this work in their everlasting salvation. (3.) The subject-matter of the promises contained in the covenant of grace, relates not only to their sanctification here, but salvation hereafter; in which respect it is called _an everlasting covenant_, and the mercies thereof, _the sure mercies of David_, Isa. lv. 3, 4. that is, either those mercies which David, who had an interest in this covenant, was given to expect; or mercies which Christ had engaged to purchase and bestow, who is here called David, as elsewhere, Hos. iii. 5. inasmuch as David was an eminent type of him, as well as because he was his seed according to the flesh; and that this is the more probable sense of the two, appears from the following words, in which he is said to be _given for a witness to the people, a leader and commander to the people_: and if these mercies are in Christ’s hand to apply, it is no wonder that they are styled _sure mercies_.