tread warily

I must tread warily,' he thought; 'that fellow could make himself very nasty.

On this point it behoves us to tread warily, and to avoid dogmatising.

She scrutinized both of us with the intuitive glance of one who has learned to tread warily amid dangerous surroundings.

Truth to tell, the department had to tread warily in stalking such big game as a Senator.

Bless your tender heart for the kind thought, but in this case it's up to me to tread warily.