Trust in him at all times - This exhortation, addressed to all persons, in all circumstances, and at all times, is founded on the personal experience of the psalmist, and on the views which he had of the character of God, as worthy of universal confidence. David had found him worthy of such confidence; he now exhorts all others to make the same trial, and to put their trust in God in like manner. What he had found God to be, all others would find him to be. His own experience of God’s goodness and mercy - of his gracious interposition in the time of trouble - had been such that he could confidently exhort all others, in similar circumstances, to make the same trial of his love.
Ye people, pour out your heart before him - All people. On the meaning of the phrase “pour out your heart,” see the notes at Psalms 42:4. The idea is, that the heart becomes tender and soft, so that its feelings and desires flow out as water, and all its emotions, all its wishes, its sorrows, its troubles, are poured out before God. All that is in our hearts may be made known to God. There is not a desire which he cannot gratify; not a trouble in which he cannot relieve us; not a danger in which he cannot defend us. And, in like manner there is not a spiritual want in which he will not feel a deep interest, nor a danger to our souls from which he will not be ready to deliver us. Much more freely than to any earthly parent - to a father, or even to a mother - may we make mention of all our troubles, little or great, before God.
God is a refuge for us - For all. For one as well as another. He is the only refuge; he is all the refuge that we need.