Laravel 5.3 eager loaded relations using method with()

I have a problem with Laravel 5.3 eager loaded relations using method with().

Either I do something wrong, or I understand it wrong.

I run this code:

$result = Post::with(['comments' => function ($query) {

    $query->where('content', 'like', '"%blanditiisx%"');

}])->get();

By checking database table 'comments' empirically, I know, that there is only single comment that has word 'blanditiisx' in its column 'content'.

So, since given comment can belong only to one post and we have only one comment matching 'where' condition, I was looking to get only one post.

To my surprise, above code returns all posts I have in database.

I would appreciate, if someone could tell me where I am going wrong with it.

---

Here is what I am working with:

---

POST

I have Post class with this relationship defined in it:

/**
 * One to Many relation
 *
 * @return \Illuminate\Database\Eloquent\Relations\hasMany
 */
public function comments()
{
    return $this->hasMany(Comment::class);
}

It works with this posts class:

+------------+------------------+------+-----+---------+----------------+
| Field      | Type             | Null | Key | Default | Extra          |
+------------+------------------+------+-----+---------+----------------+
| id         | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| created_at | timestamp        | YES  |     | NULL    |                |
| updated_at | timestamp        | YES  |     | NULL    |                |
| title      | varchar(255)     | NO   |     | NULL    |                |
| slug       | varchar(255)     | NO   | UNI | NULL    |                |
| summary    | text             | NO   |     | NULL    |                |
| content    | text             | NO   |     | NULL    |                |
| seen       | tinyint(1)       | NO   |     | 0       |                |
| active     | tinyint(1)       | NO   |     | 0       |                |
| user_id    | int(10) unsigned | NO   | MUL | NULL    |                |
+------------+------------------+------+-----+---------+----------------+

---

COMMENT

I have Comment class with this relationship defined in it:

/**
 * One to Many relation
 *
 * @return \Illuminate\Database\Eloquent\Relations\BelongsTo
 */
public function post()
{
    return $this->belongsTo(Post::class);
}

It works with this comments class:

+------------+------------------+------+-----+---------+----------------+
| Field      | Type             | Null | Key | Default | Extra          |
+------------+------------------+------+-----+---------+----------------+
| id         | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| created_at | timestamp        | YES  |     | NULL    |                |
| updated_at | timestamp        | YES  |     | NULL    |                |
| content    | text             | NO   |     | NULL    |                |
| seen       | tinyint(1)       | NO   |     | 0       |                |
| user_id    | int(10) unsigned | NO   | MUL | NULL    |                |
| post_id    | int(10) unsigned | NO   | MUL | NULL    |                |
| deleted_at | timestamp        | YES  |     | NULL    |                |
+------------+------------------+------+-----+---------+----------------+

via Chebli Mohamed