Jonathan Edwards with a timeless message on “Jesus Christ the Same Yesterday, Today, and Forever” (dated April 1738)
You may greatly comfort yourself that you have an unchangeable friend in Christ Jesus. From the unchangeableness of your Savior, you may be assured of your continuance in a state of grace. As to yourself, you are so changeable, that, if left to yourself, you would soon fall utterly away. But Christ is the same, and therefore, when he has begun a good work in you he will finish it. As he has been the author, he will be the finisher of your faith.
When once you have entered on the happiness of heaven, it never shall be taken from you, because Christ, your Savior and friend, who bestows it on you, and in whom you have it, is unchangeable. He will be the same forever and ever, and therefore so will be your happiness in heaven.
(via Of First Importance)