add_action('rest_api_init', 'prayer_request_routes');

function prayer_request_routes() {
    register_rest_route('prayerRequest/v1', '/{id}', array(
        'methods' => 'GET',
        'callback' => 'getPrayerRequestById'
    ));
}

function getPrayerRequestById() {
    global $wpdb;
    $id = $_GET['id'];
    $query = "SELECT * FROM wp_prayer_requests WHERE id = $id";
    $result = $wpdb->get_results($query);
    return $result;
}