The assurance of the believer is not that God will save him even if he stops believing, but that God will keep him believing--God will sustain you in faith, he will make your hope firm and stable to the end. He will cause you to persevere.
John PiperThere are only three kinds of Christians when it comes to world missions: zealous goers, zealous senders, and disobedient.
John PiperHusbands and wives, recognize that in marriage you have become one flesh. If you live for your private pleasure at the expense of your spouse, you are living against yourself and destroying your joy. But if you devote yourself with all your heart to the holy joy of your spouse, you will also be living for your joy and making a marriage after the image of Christ and His church.
John Piper