The king hath commanded me a business - All said here is an untruth, and could not be dictated by the Spirit of the Lord; but there is no reason to believe that David was under the influence of Divine inspiration at this time. It is well known that from all antiquity it was held no crime to tell a lie, in order to save life. Thus Diphilus: -

Ὑπολαμβανω το ψευδος επι σωτηριᾳ

Λεγομενον, ουδεν περιποιεισθαι δυσχερες.

"I hold it right to tell a lie, in order to procure my personal safety; nothing should be avoided in order to save life."

A heathen may say or sing thus; but no Christian can act thus, and save his soul, though he by doing so may save his life.

under thine

1 Samuel 21:4 And the priest answered David, and said, There is no common bread under my hand, but there is hallowed bread...

Judges 9:29 And would to God this people were under my hand! then would I remove Abimelech. And he said to Abimelech, Increase your army...

Isaiah 3:6 When a man shall take hold of his brother of the house of his father, saying, You have clothing, be you our ruler...

present [heb] found

Touching Jacob, However, that which He did at his Mother's Bidding...
24. Touching Jacob, however, that which he did at his mother's bidding, so as to seem to deceive his father, if with diligence and in faith it be attended to, is no lie, but a mystery. The which if we shall call lies, all parables also, and figures designed for the signifying of any things soever, which are not to be taken according to their proper meaning, but in them is one thing to be understood from another, shall be said to be lies: which be far from us altogether. For he who thinks this, may …
St. Augustine—Against Lying