'Slack' in the Bible

but repays those who hate Him to their faces, by destroying them; He will not hesitate with him who hates Him, He will repay him to his face.

“When you make a vow to the Lord your God, you shall not delay to pay it, for He will most certainly require it of you, and a delay would cause you to sin.

So Joshua asked them, “How long will you put off entering to take possession of the land which the Lord, the God of your fathers, has given you?

But as for you, be strong and do not lose courage, for there is reward for your work.”

Poor is he who works with a negligent and idle hand,But the hand of the diligent makes him rich.

He who is careless in his workIs a brother to him who destroys.

Now we command you, believers, in the name of our Lord Jesus Christ and by His authority, that you withdraw and keep away from every brother or sister who leads an undisciplined life and does not live in accordance with the tradition and teaching that you have received from us.