Andrew Gray (Great and Precious Promises, pp. 26, 27):
Since Christ is the Fountain and Original of the Promises, be much in the application of the promises. And here I shall speak a little upon these three things. 1. A little unto the evidences and marks of those that have a right to apply the promises, and shall only name unto these few. The first is, To be a person under convictions of sensible need and necessity of such a promise; have ye convictions of such a necessity? Then from that ye may infer, “I have a right to the promises, and are not these glad tidings? I know there are some that are under such conviction of their sins, that they think it boldness to apply the promises. But I would say this unto you, that if ye were under sensible convictions of your lostness, ye would give a world for an hair of a promise whereby to hang. Believe it, the exercise of misbelief is never at its height, till ye would be content to dig through the earth to get a promise; and till we were at that, that our souls would pursue after them from the one end of the world to the other. And for the ground of this assertion, that sensible necessity giveth a right to the promises; if ye will look to these great promises of the everlasting covenant, are they not given to that Christian that is under a need [( Isa. 55.13* and Matt. 11.28)], where the great promise of the Gospel is given out, and the invitation of Jesus Christ is unto these that are weary and heavy laden. Christ would account it an excellent courtesy, that ye should not dispute, but believe; and that ye would look upon your necessities, as his call to believe the promises.
Source: https://puritanboard.com/threads/for-those-of-us-that-can-be-too-hard-on-ourselves.95146/, Comment 7 (Poster added this note: *I think, perhaps, Mr. Gray may have meant Isaiah 55.1-3, although the use of v.13 is certainly not out of line)