I believe that this condition is common to the believer; the emptiness, and subsequent guilt at not feeling anything when in the presence of the Almighty God. We should desire to feel; to feel sorrow and guilt for our sins, for sinning against our LORD and Savior, as well as our Father. We as children seek to avoid His fatherly displeasure; there is that status as son or daughter. We should feel at times, assurance of forgiveness when we have confessed our sins and repented of them, and have pursued new obedience. When we have been delivered from some grievous sin or broken estate, we should feel the utter emptiness of our own effort, and even bewilderment when we see that we have blasphemed, and smitten with the fist of wickedness. Or like the prodigal son, when having rejected our Father, who from youth has provided for, and protected us, only to forsake our Father, yet, lo, He forgives us and utterly wipes away all memory of this, casting it behind His back, no more to be remembered. We should feel this emptiness. And joy. The joy of the Lord is a real part of the Christian's life. But truly, often the most present feeling is longing, longing to feel something. Longing to feel joy. It doesn't seem right that we shouldn't feel. But that is the life of the sinner saved. We have indwelling us the Holy Spirit, we possess new life in Christ. Yet we still inhabit these bodies of dust, and there still remains much corruption in all believers, so often shrouding the glory of Christ, casting up mud to obscure our vision. I think a question worth asking of those who give this assessment of worship: Are you here to feel, or because you feel the sense of your own unworthiness? Feeling without Christ is death, and so is the Regulative Principle of Worship death without Christ. Maybe put forth the help that they pray for God to give them this sense of their own unworthiness, that they may give all glory to God, for His deliverance. And pray for them as well. Going through the motions of worship, without the work of the Holy Spirit is the most agonizing and painful thing. One should never say worship is boring; please consider asking them what is boring about the worship service, and why they believe they don't feel God. I believe many who think this, do feel God, but they feel His wrath for their sins, and need Christ. Or they have their sins cast up by Satan to discourage them, or they see their remaining sin, and are brought low. Past life experiences of believers who may have sinned egregiously do not disappear at regeneration: we reap what we sow. But we are saved as by fire, and as the fire of the Word and Spirit burn up our dross, it is painful, and one may feel undone. This is different from simply "not feeling God". Also, in Reformed circles, we tend to become legalistic, where as Charismatic folk tend to become antinomian. They might have a true complaint. I would beg you address them in all humility, seeking how they might be built up in Christ, not debased for not conforming to Reformed standards. Above all pray for them. If you find evidence for unbelief, tell them of Christ, and the true nature of the Christian walk: our pilgrimage is not often easy. Tell them they may not feel now, but in Christ, there is rest, and that eternal, which is far more glorious than "feeling". Peace be unto you.