GOD'S WORD® Translation
They were terrified, and thought they were seeing a ghost.

American Standard Version
But they were terrified and affrighted, and supposed that they beheld a spirit.

Berean Study Bible
But they were startled and frightened, thinking they had seen a spirit.

Douay-Rheims Bible
But they being troubled and frightened, supposed that they saw a spirit.

English Revised Version
But they were terrified and affrighted, and supposed that they beheld a spirit.

King James Bible
But they were terrified and affrighted, and supposed that they had seen a spirit.

World English Bible
But they were terrified and filled with fear, and supposed that they had seen a spirit.

Young's Literal Translation
and being amazed, and becoming affrighted, they were thinking themselves to see a spirit.

Luke 24:37 Additional Translations ...