Albert Barnes Commentary Psalms 37:26

"All the day long he dealeth graciously, and lendeth; And his seed is blessed." — Psalms 37:26 (ASV)

He is always merciful - Margin, as in Hebrew, “all the day.” That is, it is his character; he is constantly in the habit of showing kindness. He does not do it at intervals, or only occasionally, but this is what marks his character. He is known by this. The word “merciful” here means kind, compassionate, benignant—especially in his willingness to “lend” to others when he has the means.

And lends - The wicked man “borrows,” but does not pay again (Psalms 37:21); the righteous man “lends” to his neighbor.

And his seed is blessed - His children; his posterity, as the result of this conduct on his part. The effect of what he does passes over from him to them, conveying rich blessings to them.