Psalms 37:31

29 The righteous will inherit the land and dwell in it forever.

30 The mouth of the righteous man utters wisdom, and his tongue speaks justice.

The law of his God is in his heart; his steps do not falter.

32 Though the wicked lie in wait for the righteous, and seek to slay them,

33 the LORD will not leave them in their power or let them be condemned under judgment.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
The law of his God is in his heart; his steps do not falter.
KJV
The law of his God is in his heart; none of his steps shall slide.
WEB
The law of his God is in his heart. None of his steps shall slide.
ASV
The law of his God is in his heart; None of his steps shall slide.
DARBY
the law of his God is in his heart; his goings shall not slide.
BLB
The law of his God [is] in his heart; his steps do not slip.
ÅB
Hans Guds lov er i hjertet hans;
trinnene hans vakler ikke.
OTB
Deres Guds lov er i deres hjerter;
Deres skritt vakler ikke.
B1930
Hans Guds lov er i hans hjerte, hans trin vakler ikke.

Study notes (Tyndale)

Original text and word study

Cross references