To fail to associate ourselves in a lasting and committed way with the Head of the church by joining his body is surely a sign of ingratitude, whether from an uninformed or a dull heart. We who have the privilege of living in countries where we may freely join a local church should keep this admonition from Dietrich Bonhoeffer in mind:
It is by the grace of God that a congregation is permitted to gather visibly in this world to share God’s Word and sacrament. Not all Christians receive this blessing. The imprisoned, the sick, the scattered lonely, the proclaimers of the Gospel in heathen lands stand alone. They know that visible fellowship is a blessing. They remember, as the Psalmist did, how they went “with the multitude…to the house of God, with the voice of joy and praise, with a multitude that kept holyday” (Ps.42:4)…Therefore, let him who until now has had the privilege of living in common Christian life with other Christians praise God’s grace from the bottom of his heart. Let him thank God on his knees and declare: It is grace, nothing but grace, that we are allowed to live in community with Christian brethren.
Thabiti Anyabwile, What is a Healthy Church Member?, (pgs. 70-71) quote from Dietrich Bonhoeffer, Life Together.