laravel select all row from 3 table

What could I do to select all column 1 row from 3 table in laravel 5.4 ?

I want to select posts, comments , users where post_id = comment.post_id and comment.user_id = user.id.

show it in single page post with post_title, Comment By username

I has 3 table like this

Schema::create('posts', function (Blueprint $table) {
      $table->increments('id');
      $table->text('title');
      $table->longText('description');
      $table->text('image');
      $table->timestamps();
});

Schema::create('comments', function (Blueprint $table) {
      $table->increments('id');
      $table->longText('comment');
      $table->integer('user_id');
      $table->integer('post_id');
      $table->timestamps();
});

Schema::create('users',function (Blueprint $table){
      $table->increments('id');
      $table->string('username',30)->unique();
      $table->string('email')->unique();
      $table->string('password',60);
      $table->rememberToken();
      $table->timestamps();
});

thank for your answer.

via Chando