John Calvin Commentary Psalms 68:13

"When ye lie among the sheepfolds, [It is as] the wings of a dove covered with silver, And her pinions with yellow gold." — Psalms 68:13 (ASV)

Though you should lie among the pots. Having spoken of God as fighting the battles of His people, the psalmist adds, by way of qualification, that they may remain for a time in darkness, though God will eventually appear for their deliverance. There can be little doubt that the psalmist hints at the state of wretchedness and distress to which the nation had been reduced under the government of Saul, for this intervention was all the more remarkable, considering the misery from which it had emerged.

These words, however, convey a further instruction than this. They teach us the general truth that believers, by the hidden and mysterious power of God, are preserved unhurt in the midst of their afflictions, or are suddenly recovered so that they exhibit no marks of them. This language can be interpreted to mean either that they shine even when lying under filth and darkness, or that, when freed from their troubles, they shake off any defilement they may have contracted. Whichever interpretation is adopted, it remains true that the believer is never consumed or overwhelmed by his afflictions, but emerges safe. An elegant figure is drawn from the dove, which, though it may lie among the pots, retains the beauty which naturally belongs to it and contracts no defilement on its wings. From this we learn that the Church does not always present a fair or peaceful aspect, but rather emerges occasionally from the darkness that envelops it, and recovers its beauty as perfectly as if it had never been subjected to calamity.