That is a good question. I think a fair answer is that God's revealed will covers a great spectrum of things. Probably no child of God is walking with God in every spectrum. For example, there are children of God within the Great Whore (Rev. 18:4) and yet that does not mean they are outside of God's will in all other areas of life. There are no doubt paedobaptists who are genuinely saved and with regard to personal sanctification may be walking closer to God than you or I. In the area of church truth they are obviously not walking with God with regard to the ordinances or the nature of a NT church.so my question is, how can someone who disagrees with someone on so many levels be in the Will of God (regardless of who the person is), unless the question at hand isn't profitable to begin with?
Again, personal worship is quite different than public worship as public worship requires a completely additional spectrum.