Salvation is only one purpose of the grace that is given to us, and not the primary purpose at that. It was a necessary first step to reconcile man with God so that all other purposes can be accomplished, culminating in the primary purpose of glorifying God. Participating regularly in the diligence J.C. Ryle describes is participating in all the purposes of grace beyond salvation, which is already considered complete.
The verse about losing your first love comes to mind; having just celebrated our 20th anniversary, I can honestly say that my relationship with my wife has not always been as close and loving as it ought. If I do not work at it, die to self, distance creeps in. But the marriage covenant we entered is never broken, nor was it contingent on a perpetual state of being "in love". Since marriage is the illustration given to us of our relationship with Christ, and we the bride are called to love the groom, its evident that daily communion with our beloved, keeping ourselves pure, reading (and rereading) His letters to us, is appropriate behavior to keep the relationship strong and healthy.
My son has found the one for him (She's in MT, we're in VA), and they're in that disgustingly sweet phase of the relationship where they might actually die if they're not in communication, if they don't talk to each other every day, or get an letter, text or email. And when they're together, they're never more than arms length away. Right now its not a burden for them to prioritize their relationship, and spend time on it because its their first love. Sorta reminiscent of a new believer, isn't it? Can't get enough of Jesus, His Word, or fellowship with other believers. Remember that feeling?
