Ittakhathoo aymanahum junnatan fasaddoo AAan sabeeli Allahi innahum saa ma kanoo yaAAmaloon (surah Munafiqun: 2)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(63:2) They shelter behind their oath, *2 and thus hinder their own selves and others from the Path of Allah. *3 Evil indeed is what they do.

Ittakhazoo aymaanahum junnatan fasaddoo `an sabeelil laah; innahum saaa`a maa kaanoo ya`maloon

*2) That is, they use the oaths that they swear to convince others of their Islam and faith as a shield to save themselves from the wrath of the Muslims so that they do not treat them as they treat their open enemies.
These oaths may imply the oaths which they usually swear to convince others of their faith as well as those which they swore when they were caught committing some hypocritical act, and also those oaths which 'Abdullah bin Ubayy had sworn to contradict the report given by Hadrat Zaid bin Arqam. Besides these, there is another probability that Allah might have regarded this statement of theirs as an oath: "We bear witness that you are Allah's Messenger." This last probability has given rise to a dispute among the jurists, namely: If a person states something with the words: "I bear witness," will it be regarded as an oath or not? Imam Abu Hanifah and his companions (except Imam Zufar), Imam Sufyan Thauri and Imam Auza'i regard it as an oath (Yamin in the Shari'ah terminology). Imam Zufar says that it is not an oath. Two sayings from Imam Malik have been reported in this connection: first' that it is an oath absolutely, and second, that if while saying: "I bear witness," his intention was to say: y God, I bear witness," or "I bear witness before God," it would he a statement on oath, otherwise not. Imam Shafe'i says: 'Even if the person says the words: "I bear witness before God." it would not be a statement made on oath, unless he uttered these words with the intention of swearing an oath," (AI-Jassas_, Ahkam al-Qur an; Ibn al'.Arabi. Ahkam al-Qur an).
*3) The verb sadd in Arabic is transitive as well as intransitive. Therefore, saddu 'an sabil-Allah means; "They turn away from the Way of Allah," as well as: 'they turn others away from the Way of AIIah." According to the first meaning the verse would 'mean: "By means of these oaths they first plant themselves firmly among the Muslims and then invent ways to escape fulfilling demands of the faith and to avoid obedience to AIlah and His Messenger. " According to the second meaning it would mean: "They use their false oaths as a cover for committing evil deeds. Posing as Muslims they weaken the Muslim community from within: find out the secrets of the Muslims and convey these to their enemies, create doubts about Islam among the non-Muslims and use such devices for inspiring the simple Muslims with evil suggestions which a hypocrite in the guise of a Muslim only could do, for an open enemy of Islam cannot use them.