If we are doing all we can, if we are maxed out, then of course it is not necessary to do what we simply cannot do. But we should not kid ourselves in this regard. We often have hidden reserves that even we do not suspect. Setting ambitious goals is therefore a good thing, and determining whether or not we are desiring something sinful, or desiring it sinfully, is heart work. We do that heart work by praying to the Lord about it, by reading the Word faithfully, looking to be instructed, and by worshiping God together with His people, gathering regularly to be edified by Word and sacrament.
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