You asked how I read Hebrews 10:25.I read it as a clear exhoration for us to meet as a group on a regular basis.
You asked ,"What is an elder?". See Titus 1:5-9.
1 Cor.12:7 speaks of how we should use our spiritual gift.It plainly tells us that our gift was given to profit withal (to benefit the body).How can we be obedient to this command if we don't meet as a group?
Also, I agree with Tom in respect to Baptism and Communion.

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