[19].Surah Maryam [Mary]: Ayat 1-3

Ayat 1. Kâf-Hâ-Yâ-'Aîn-Sâd. [These letters are one of the miracles of the Qur'an, and none but Allah (Alone) knows their meanings].

Ayat 2. (This is) a mention of the mercy of your Lord to His slave Zakariya (Zachariah).

Ayat 3. When he called out his Lord (Allah) a call in secret,

[Tafseer] This is Makki contain 98 Ayats its the only Surah which begins with these five Abbreviated Letters, Kaf, Ha Ya 'Ayn, Sad. For Abbreviated Letters generally, As stated, such Letters are Symbols, of which the true meaning is known to Allah alone. We should not be dogmatic about any conjectures that we make. The Mercy of Allah to Zakariya was shown in many ways: (1) in the acceptance of his prayer; (2) in bestowing a son like Yahya; and (3) in the love between father and son, in addition to the work which Yahya did as Allah's Messenger for the world. There the public ministry was the point stressed; here the beautiful relations between the son and the father. In secret: because he feared that his own family and relatives were going wrong (19:5), and he wanted to keep the lamp of Allah burning bright. He could not very well mention the fear about his colleagues (who were his relations) in public.  

 Hazrat Anas (May Allah be pleased with him) said: The Messenger of Allah  [SAWW] (PBUH) said, "When one of you supplicates, let him be decisive and he should not say: `O Allah, bestow upon me such and such if You wish', because no one has the power to compel Him.''
[Al-Bukhari Book 08, Chapter 75, Hadith # 350].

Lesson : as mentioned above in Surah Maryam Ayat 03."When he called out his Lord (Allah) a call in secret" One should pray to Allah will full confidence that He will answer his prayers. One should also persist in praying and never give in to despair.