It's such a shame, then, that the second half of the psalm spoils it, dissipates the warm glow and dampens the elevated spirit, as it moves from the call to worship to the clearest warning: "Don't harden your hearts."
The change of tenor and tone of voice is quite disturbing. A dark cloud has now crossed the face of the sun, a sinister chill has fallen and it feels like it's time to pack up and go inside. Such a shame, we were having a lovely morning.
Why the warning? And why does it so disturb and even disappoint us?
The Psalms aren't only for our comfort, they're also for our instruction and training in righteousness. They're scripture, after all. And the placement of this warning is inspired.
It reminds us of our continuing vulnerability to sin, even if we've been Christians for many years. If we're tempted to think, 'That's not me', we need to see how the psalm lays down a continuity between the people it was written to and those of the wilderness generation it refers to: "As you did...in the wilderness." They hadn't been there in person but they were of the same spirit, in the same need, from the same broken human stock.
Sometimes we close the door of our hearts to the Lord and his voice because of the weight of disappointment and duress we have known. Where is the promise, now, that he will not forsake us or let us down?
At other times, the slow-burn of temptation catches and begins to blaze and we find we're on the cusp of giving in to it. But how could we do that when we know Jesus has so loved us? By hardening our hearts, bolting the door.
Or we harden ourselves through small, decisive choices. They're barely visible to the naked eye, adjusting the set of our hearts by tiny degrees, but the long-term effect is to take us completely off course.
We need the warning.
But it's no accident that it comes after the opening half of the psalm, where the worship is sincere and compelling. Praise and the unfolding of the greatness of God - his person and work - are the necessary counterpoint to the urgent warning.
The psalm is calling us to join in the song of praise, to come with thanksgiving and joyful gladness. Taking up that call has the capacity to re-order and reclaim our hearts, to keep them from the deadening deceitfulness of sin.
And, like the pure nard that Mary lavished on our Lord Jesus in readiness for his death, such devotion reaches others - "the whole house was filled with its fragrance" - and helps to sustain within each of us a softness and responsiveness of heart.
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My eyes are dry,
My heart is hard,
And I know how
Alive to you
Soften it up
The oil is you,
Please wash me anew,
Keith Green (1958-82)