The Bible instructs us to judge their words, especially concerning grace, but ultimately leaves the judgment of individuals' hearts to God.
The Bible teaches that while we can and should judge someone's words, especially when it pertains to the grace of God, we must refrain from making final judgments about the condition of their hearts. As mentioned in II Thessalonians 3:14-15, we are encouraged to regard those who may err in doctrine as brethren, emphasizing a spirit of charity in our judgments. The capacity to judge accurate doctrine does not equate with knowing the true spiritual state of an individual, as even the most learned believers can misstate divine truths at times.
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