Truth, sincerity, etc.

Phil. 4:8.

Let those who bear the Christian name
Their holy vows fulfil;
The saints, the followers of the Lamb,
Are men of honor still.

True to the solemn oaths they take,
Though to their hurt they swear;
Constant and just to all they speak,
For God and angels hear.

Still with their lips their hearts agree,
Nor flatt'ring words devise;
They know the God of truth can see
Through every false disguise.

They hate th' appearance of a lie
In all the shapes it wears;
They live in truth, and when they die,
Eternal life is theirs.

While hypocrites and liars fly
Before the Judge's frown,
His faithful friends, who fear a lie,
Receive th' immortal crown.

Isaac Watts

http://www.poemhunter.com/poem/hymn-35-part-2/