Be of the opinion that…
Definition 1 of 1
Pro Tip 1/3Subjectivity
Expresses a personal belief, not a fact, and invites others to agree or disagree. 
She was of the opinion that the test was too difficult, but others may not think so.
Pro Tip 2/3Formal Tone
Often used in formal or professional contexts to sound more thoughtful or respectful. 
The committee is of the opinion that the current policy should remain unchanged.
Pro Tip 3/3Respectful Disagreement
Useful for politely expressing a differing viewpoint in a debate or discussion. 
While I respect your view, I am of the opinion that we should reconsider our approach.