Such a link may arise either as a result of the nature of the activity , for example where it involves taking part in the determination of the ethos of the church or organisation in question or contributing to its evangelising mission , or of the circumstances in which the activity is to be carried out , for instance , where it is necessary to ensure that the church or organisation is presented in a credible fashion to the outside world ( see , to that effect , judgment of 17 April 2018 , Egenberger , C ‑ 414 / 16 , EU : C : 2018 : 257 , paragraphs 62 to 63 ) . 51 More specifically , with respect to the three criteria laid down in the first subparagraph of Article 4 ( 2 ) of Directive 2000 / 78 , the Court has stated , first of all , that the use of the adjective ‘ genuine ’ means that professing the religion or belief on which the ethos of the church or organisation is founded must be necessary because of the importance of the occupational activity in question for the promotion of that ethos or the exercise by the church or organisation of its right of autonomy , as recognised by Article 17 TFEU and Article 10 of the Charter ( see , to that effect , judgment of 17 April 2018 , Egenberger , C ‑ 414 / 16 , EU : C : 2018 : 257 , paragraphs 50 and 65 ) . 52 The Court then noted that use of the term ‘ legitimate ’ shows that the EU legislature intended to ensure that the requirement of professing the religion or belief on which the ethos of the church or organisation is founded is not used to pursue an aim that has no connection with that ethos or with the exercise by the church or organisation of its right of autonomy ( judgment of 17 April 2018 , Egenberger , C ‑ 414 / 16 , EU : C : 2018 : 257 , paragraph 66 ) . 53 Lastly , the term ‘ justified ’ implies not only that a national court can review whether the criteria laid down in Article 4 ( 2 ) of Directive 2000 / 78 are being complied with , but also that the church or organisation imposing the occupational requirement is obliged to show , in the light of the factual circumstances of the individual case , that the alleged risk of undermining its ethos or its right of autonomy is probable and substantial , so that the imposition of such a requirement is necessary ( see , to that effect , judgment of 17 April 2018 , Egenberger , C ‑ 414 / 16 , EU : C : 2018 : 257 , paragraph 67 ) . 54 In that regard , the requirement in the first subparagraph of Article 4 ( 2 ) of Directive 2000 / 78 must be consistent with the principle of proportionality , which means that the national courts must ascertain whether the requirement in question is appropriate and does not go beyond what is necessary for attaining the objective pursued ( judgment of 17 April 2018 , Egenberger , C ‑ 414 / 16 , EU : C : 2018 : 257 , paragraph 68 ) . 55 It follows from the considerations set out in paragraphs 49 to 54 above that a church or other public or private organisation the ethos of which is based on religion or belief can treat its employees in managerial positions differently , as regards the requirement to act in good faith and with loyalty to that ethos , depending on their affiliation to a particular religion or adherence to the belief of that church or other organisation only if , bearing in mind the nature of the occupational activities concerned or the context in which they are carried out , the religion or belief is a genuine , legitimate and justified occupational requirement in the light of that ethos . 56 In that regard , while it is ultimately for the national court , which has sole jurisdiction to appraise the facts , to determine whether requiring only employees in managerial positions who share the religion or belief on which the church or organisation concerned is based to act in good faith and with loyalty is in fact a genuine , legitimate and justified occupational requirement within the meaning of the first subparagraph of Article 4 ( 2 ) of Directive 2000 / 78 , the Court may nevertheless provide guidance , based on the file in the main proceedings and the written and oral observations submitted to it , in order to enable the national court to give judgment in the particular case before it . 57 In the present case , the requirement at issue in the main proceedings concerns the respect to be given to a particular aspect of the ethos of the Catholic Church , namely the sacred and indissoluble nature of religious marriage . 58 Adherence to that notion of marriage does not appear to be necessary for the promotion of IR ’ s ethos , bearing in mind the occupational activities carried out by JQ , namely the provision of medical advice and care in a hospital setting and the management of the internal medicine department which he headed .