He is a suitable man for any post.
He is a man suitable for any post.
Which of the following sentences is correct? What is the difference in meaning between these?
Both are correct and have the same meaning.
'Suitable' here is used an an attributive adjective. These adjectives can appear before or after their noun, but if they appear after, you must include their complement ('for any post' in this case) immediately afterwards. For example:
Q: "Is General MacArthur suitable for a post in the Philippines?"
A: "He is a man suitable for any post." (correct)
A: "He is a suitable man for any post." (correct)
A: "He is a suitable man." (correct)
A: "He is a man suitable." (incorrect as the complement is missing)