Albert Barnes Commentary Psalms 29:11

"Jehovah will give strength unto his people; Jehovah will bless his people with peace." — Psalms 29:11 (ASV)

The Lord will give strength unto his people - This is a practical application of the sentiments of the psalm, or a conclusion that is fairly derived from its main thought. The idea is that the God who presides over the tempest and the storm—the God who has such power and can produce such effects—is abundantly able to uphold His people and defend them. In other words, the application of such amazing power will be to protect His people and save them from danger.

When we look at the rolling clouds in the tempest, hear the roaring of the thunder, see the flashing of the lightning, hear the oak crash on the hills, and see the waves piled mountains high—if we feel that God presides over all and controls all this with infinite ease—we certainly have no reason to doubt that He can protect us. We have no reason to fear that His strength cannot support us.

The Lord will bless his people with peace - They have nothing to fear in the tempest and storm; nothing to fear from anything. He will bless them with peace in the tempest; He will bless them with peace through that power by which He controls the tempest. Let them, therefore, not fear in the storm, however fiercely it may rage; let them not be afraid in any of the troubles and trials of life.

In the storm, and in those troubles and trials, He can make the mind calm. Beyond those storms and those troubles, He can give them eternal peace in a world where no “angry tempest blows.”