David de Bruyn has some very good and helpful thoughts here on the intersection of private worship, what he calls “perpetual worship,” and corporate worship (unless I misunderstand it, I would probably add the category of ‘family worship’ to this triad). You might recall (but probably don’t) that I made similar comments on this subject here (some of which I would probably say a bit differently now, though the whole of it I still stand by).
His comments struck me, as I had just read this morning a passage in Edwards concerning the importance of private worship, which I do affirm is important in the Christian life of the believer. Edwards insists that the true believer thrives on both Christian society and private communion with God, so that both are proportioned fittingly one to the other:
True religion disposes persons to be much alone, in solitary places, for holy meditation and prayer. . . .
’Tis difficult to conceal great affections, but yet gracious affections are of a much more silent and secret nature, than those that are counterfeit. . . .
The most eminent divine favors that the saints obtained, that we read of in Scripture, were in their retirement. . . .
But this is all that I am at by what has been said, to shew that it is the nature of true grace, that however it loves Christian society in its place, yet it in a peculiar manner delights in retirement, and secret converse with God. So that if persons appear greatly engaged in social religion, and but little in the religion of the closet, and are often highly affected when with others, and but little moved when they have none but God and Christ to converse with, it looks very darkly upon their religion.” Religious Affections, 2:374-6.
To these comments Edwards appends the following remarks by some other Puritans:
“The Lord is neglected secretly, yet honored openly; because there is no wind in their chambers to blow their sails; and therefore there they stand still. Hence many men keep their profession, when they loose their affection. They have by the one a name to live (and that is enough), though their hearts be dead. And hence so long as you love and commend them, so long they love you; but if not, they will forsake you. They were warm only by another’s fire, and hence having no principle of life within, soon grow dead. This is the water that turns a Pharisee’s mill.” (Citing The Parable of the Ten Virgins.)
“The hypocrite is not for the closet, but the synagogue; Matt 6:5-6: ‘Tis not his meat and drink to retire from the clamor of the world, to enjoy God in secret.” (Citing the Touchstone of Sincerity.)
Sincerity may be determined when “persons be obedient in the absence, as well as in the presence of lookers-on; in secret, as well, yea more than in public.” (citing Cases of Conscience)