All genuine religion involves a quest since God must remain largely unknown, and this by his very nature. He must remain latens Deitas in Aquinas' phrase:
Adoro te devote, latens Deitas, Quæ sub his figuris vere latitas;
Tibi se cor meum totum subjicit, Quia te contemplans totum deficit.
Godhead here in hiding, whom I do adore, Masked by these bare shadows, shape and nothing more, See, Lord, at Thy service low lies here a heart Lost, all lost in wonder at the God thou art.
(tr. Gerard Manley Hopkins, here.)
But as religion becomes established in the world in the form of churches, sects, and denominations with worldly interests, it becomes less of a quest and more of a worldly hustle. Dogmatics displaces inquiry, and fund-raising faith. The once alive become ossified.
Mature religion must be more quest than conclusions. It is vastly more a seeking than a finding. More a cleansing of windows and a polishing of mirrors than a glimpsing. And certainly more a glimpsing than a comfortable resting upon dogmas. Perhaps when religion and philosophy are viewed as quests they merge into one another. (But compare Leo Strauss on the tension between Athens and Jerusalem!)
The critic of religion wants to pin it down, reducing it to dogmatic contents, so as to attack it where it is weakest. Paradoxically, the atheist 'knows' more about God than the sophisticated theist -- he knows so much that he knows no such thing could exist. He 'knows' the divine nature and knows that it is incompatible with the existence of evil -- to mention one line of attack. Aquinas, by contrast, held that the existence of God is far better known than God's nature -- which remains shrouded in a cloud of unknowing.
The religionist also wants religion pinned down and dogmatically spelled out for purposes of self-definition, doxastic security, other-exclusion, worldly promotion and political leverage. This is a reason why reformers like Jesus are met with a cold shoulder -- or worse.