New Living Translation
Happy is the one who takes your babies and smashes them against the rocks!

American Standard Version
Happy shall he be, that taketh and dasheth thy little ones Against the rock.

Berean Study Bible
Blessed is he who seizes your infants and dashes them against the rocks.

Douay-Rheims Bible
Blessed be he that shall take and dash thy little ones against the rock.

English Revised Version
Happy shall he be, that taketh and dasheth thy little ones against the rock.

King James Bible
Happy shall he be, that taketh and dasheth thy little ones against the stones.

World English Bible
Happy shall he be, who takes and dashes your little ones against the rock. By David.

Young's Literal Translation
O the happiness of him who doth seize, And hath dashed thy sucklings on the rock!

Psalm 137:9 Additional Translations ...