King James Bible
For if God spared not the natural branches, take heed lest he also spare not thee.

New King James Version
For if God did not spare the natural branches, He may not spare you either.

American Standard Version
for if God spared not the natural branches, neither will he spare thee.

Berean Study Bible
For if God did not spare the natural branches, He will certainly not spare you either.

Douay-Rheims Bible
For if God hath not spared the natural branches, fear lest perhaps he also spare not thee.

English Revised Version
for if God spared not the natural branches, neither will he spare thee.

World English Bible
for if God didn't spare the natural branches, neither will he spare you.

Young's Literal Translation
for if God the natural branches did not spare -- lest perhaps He also shall not spare thee.

Romans 11:21 Additional Translations ...